105th Shock Troops Division

The 105th Shock Troops Division is an Orbital Drop Shock Troops special warfare force of the UNSC Marine Corps, Marine Corps Forces Special Warfare Command, and XLVII Shock Troops Corps. The division conducts missions for Naval Special Warfare Command through UNSC regional and space regions. Known as one of the most elite fighting forces in the UNSC Armed Forces, the 105th Shock Troops Division has participated in many battles and campaigns throughout its years of service. The 105th Shock Troops Division is also known as the Helljumpers and their insignia is a "Gold Comet."

Mission
The 105th's mission is to provide a special warfare force to accomplish special operation missions assigned by Naval Special Warfare Command and Regional Combatant Commander through their Theater Special Warfare Command. The Marines within the 105th are to assist with a variety of directives that range from direct contact with enemy troops to training colonial militias in special operation techniques. The 105th Shock Troops Division coordinates their deployments with Naval Special Warfare Command, with engagement priorities throughout their assigned regional command. Along with their main military mission focus, the 105th is capable of providing Personal Protective Details to Government Officials, Peacetime Foreign Internal Defense, along with Reconnaissance and Security Assessments on UNSC Facilities. Due to the status of the 105th, the Division is often called upon for their services given their effectiveness. ODSTs who wished to conduct Tours of Duty in specialized units often go through extensive training on top of their previous training to help build better understandings of their tasks. They remain primarily focused on FLEETCOM Sector ONE unless ordered otherwise.
 * Direct Action
 * Hostage Rescue
 * Special Reconnaissance
 * Shock Infantry
 * Counter-Terrorism
 * Counter-Insurgency
 * Counter-Contraband
 * Counter-Proliferation
 * Personnel Recovery

Organization
Under the command of a two-star General, the 105th Shock Troops Division has four active-duty Shock Troops Regiments that can conduct special warfare operations. Each Shock Troops Regiment is led by a Colonel who oversees operations throughout the Battalions, Companies, and Platoons under their command. A Lieutenant Colonel leads a Shock Troops Battalion, there are four Battalions under each Regiment. Shock Troops Companies are led by a Major and there are four Companies under each Battalion. A newly promoted Captain and 1st Lieutenant lead a Platoon; there are four platoons with each company.

A Combat Team consists of seven to ten ODSTs and can be split into Combat Element Teams. Combat Team Leaders range from Staff Sergeant to Gunnery Sergent based on the team capabilities and mission set. Combat Element Team Leaders can be Sergeants to Staff Sergeants, with a rare exception of Corporal being a Combat Element Team Leader. Unique Combat Teams such as a Special Purpose Combat Team are special assignments within the Division that are led by more senior personnel. Master Sergeants and Gunnery Sergeants with previous Combat Team Leadership deployments take command of Special Purpose Combat Teams where they conduct sensitive missions on behalf of the Division.

The Division Headquarters Battalion is considered the nucleus of the Division which oversees the entire Division. Each Regiment and Battalion have a Headquarters and Service Company. In contrast, Companies have a Headquarters and Service Platoon to assist the command and control element with overseeing operations and missions. The Staff of a Platoon or Company is broken down into Sections to help maintain the operational forces. The Staff often consists of Personnel, Intelligence, Operations, Logistics, Plans, and Communications. Other staff can include Chaplain and Legal. In the event of augmenting units from the Support Group, Light Armored Reconnaissance, Force Reconnaissance/ODST, and Space Assault Battalion, each Regiment is capable of becoming a Regimental Combat Team which is led by the Regiment Commander.

The 105th Shock Troops Support Group is led by a Colonel and assists with assigning ODST Combat Service Specialists who specialize in fields like logistics and transportation along with ODST Capabilities Specialist who assist with intelligence, fire mission support, Explosive Ordnance Disposal and, a variety of other fields. Each Shock Troops Regiment has its own Support Group Battalion to staff enablers with platoons. The 105th Shock Troops Training Center is led by a Lieutenant Colonel who oversees the training of potential Marines to join the 105th Shock Troops Division and existing members who wish to attend more courses and schools to enhance their career as an ODST. The 105th Shock Troops Light Armored Reconnaissance Battalion is a Light-Armored Vehicle Battalion capable of providing forward vehicular reconnaissance and capable of providing fire support for other vehicle battalions nearby. The 105th Force Reconnaissance/ODST and 105th Space Assault Battalion are the two special operations capable battalions assigned to the 105th Shock Troops Division. Both focus on mission-specific deployments to assist the command when they are deployed with a Marine Expeditionary Unit as an ODST Special Purposes Force or with a 105th Shock Troops Battalion.

The 105th Shock Troops Combat Development Center is considered the nucleus of providing innovative and cutting-edge equipment to the 105th Shock Troops Division. The unique Center specializes in developing tailored needs for the 105th. The Center holds military personnel, civilians, and contractors to enable the Division's combat capabilities. The Center is broken down into Sections that focus on: Capability Integration, Command, Control, Computer, and Communication, Digital Application, Intelligence Systems and Sensors, Mobility Systems, Soldier Systems, and Target Enhancements. The Center itself is led by a Lieutenant Colonel or a civilian equivalent with Majors and civilian equivalents leading each Section.

Activation and Settlement
Following the colonization of Reach in 2362, the Commandant of the Marine Corps, Commanding General of Marine Corps Forces Special Warfare Command, and Commanding General of the ODSTs held a joint meeting with their staff to discuss the establishment of a Shock Troops Division in the Epsilon Eridani system. The three Generals expressed their desire to have a Shock Troops Division located at a strategic location to respond to threats that a Sol system Shock Troops Division was not capable of responding to in time. An officer from the ODST's staff suggested the 105th Shock Troops Division as its name and soon, the 105th Shock Troops Division began its preparations for becoming the first Marine Special Warfare Force unit to settle in the Epsilon Eridani system.

Backlash within ODST Headquarters and MARSOC was met with opponents since there were enough ODST Divisions in the Sol system and it was much easier to move a reserve unit out instead of creating an entirely new active-duty SOF fighting force. However, support came from the Office of Naval Intelligence's Section One who found the idea to be smart and calculated due to the possible threats that could come about and the response time of the 105th to a threat. The Colonial Military Administration also showed support to the idea for having an elite unit to train colonists that join the ranks. Supporters won their arguments on response time, protecting civilians from unknown threats, and acting as a vanguard to the system. Unified Ground Command and Special Warfare Command feared that a unit out in the colonies would force them to spend more budget on maintaining a special operation fighting force that seemed to, on paper, pose no strategic value. With consistent backlash and support, the 105th Shock Troops Division ultimately made its way to the UNSC High Command to determine its activation in 2365.

In 2366, HIGHCOM authorized the activation of the 105th Shock Troops Division within the ODST Headquarters. The 2nd, 9th, and 19th Shock Troops Regiment moved under the banner of the new Division as logistical measures were put in place for the 105th to move out to Reach. The 105th Shock Troops Support Group and Training Center became the first subordinate units to assist the Division's Headquarters in supporting operations along with training ODSTs. For the rest of the decade, the 105th continued to build its ranks as it prepared to leave the Sol System by 2370 to settle on Reach.

The UNSC put together Task Force Voyager to help establish the first few military units in a strategic location, the 105th worked closely with the 5th Interstellar Fleet to ensure safe travel for all cargo and passengers. Planners concluded land near the Highland Mountains to serve as the military installation for the Task Force and the UNSC coordinated its efforts to secure the area in preparation with the CMA. Over 60,000 people, including families, military personnel, and contractors prepared for their voyage to the Epsilon Eridani which kicked off in 2369. The 105th Shock Troops Division and other UNSC elements spread out elements of their troops across the ships to act as security against pirates and other threats encountered along the way. The voyage itself took nearly ten months for the Task Force to arrive at the Epsilon Eridani system.

Arriving at the system in 2370, the 105th Shock Troops Division conducted environmental reconnaissance and provided security for the logistics brigade to build settlements for everyone. The 105th HQ Battalion worked with the local CMA detachment to get a feel for the system and the current situation while the rest assisted with the building of Camp Hathcock and Independence. Following the establishment of the bases, the 105th provided security for the families moving within the walls while the rest continued to establish a defined perimeter to protect the newly build military bases. The 9th Shock Troops Regiment assisted at Tribute as the 19th Shock Troops Regiment protected Circumstance. As Task Force Voyager battleships formed two patrol battlegroups, the 2nd Shock Troops Battalion of the 2nd Shock Troops Regiment took the first rotation as the rest continued with building, ground security, and humanitarian assistance.

Epsilon Eridani Conflicts
In 2376, the 105th joined a Joint Task Force - Reach to provide security and de-escalate the Settlement Skirmishes happening across Reach with the CMA. The 9th Shock Troops Regiment deployed two battalions to New Alexandria while another two were sent to Manassas. The forces conducted security patrols alongside the CMA throughout the areas and often did joint operations to prevent major conflict. Following an attack on Quezon, the 105th planned and executed a high-value target operation with help from the CMA outside of Sopron. Taking down the Diaspora leadership in the middle of 2377 ended the Settlement Skirmishes on Reach. Despite the end, the 105th continued to deploy their forces across Reach to provide security with the CMA. The cooperation between the UNSC and CMA began to build throughout the consistent patrols conducted together.

Throughout the rest of the 70s, the 105th Shock Troops Division built their numbers to add more assets to their numbers, conducted capability exercises with the armed forces, and trained with the CMA in conducting operations. Being stationed on Reach, the 105th forward deployed two battalions to Tribute and Circumstance to act as a Crisis Response Force, while another served aboard ships to conduct counter-piracy and interdiction operations for six months. In the later part of the decade, the 105th served as personal security details to CAA liaisons to ensure their protection throughout their travels within the system. At the start of 2380, Task Force Voyager began to disband as the UNSC formalized many of their unified commands among the system's space and occupied planets.

In 2381, NAVCOM stood up a counter-insurgency role known as the Reach Planetary Security Forces/Regional Stability Operations and assigned four regional command and control commands across the colony. Staffed with personnel from CMA and NAVCOM, the 105th joined as the NAVSPECWAR element to support special warfare operations across the four regions. When a regiment deployed, each battalion was sent off to Command and Control North, Command and Control East, Command and Control South, and Command and Control West. The forces participated in a variety of peacekeeping roles while also focusing on security force assistance, counter-terrorism, hostage rescue, and high-value target apprehension. Companies deployed to hot zones where Reachers and Reavians remained in scattered conflicts over land. From 2381 to 2384, the 105th provided crucial security for regional meetings to secure peace and cooperation between the two groups.

Throughout the rest of the 2380s, the 105th conducted long-range reconnaissance patrols and counter-insurgency missions. In 2387, an inspection report noted the 105th's ability to prevent terrorist attacks from happening. Utilizing all-source intelligence from the UNSC and CMA, the 105th was able to deploy platoons to deter and capture personnel planning an attack before it happened. During a raid in 2387, a suicide bomber detonated while the 105th was entering the house and resulted in the loss of a squad. It was the biggest loss of the 105th during the conflict. In 2393, there was a brief outbreak of skirmishes between Reachers and Reavians but the 105th responded in-force to prevent further violence from growing. Tribute and Circumstance had skirmishes from time to time where the 105th deployed ODST Operational Advisory Teams to embed with CMA detachments to support combat and peacekeeping operations. RPSF/RSO remained the template for the CMA and UNSC command and control of Reach till the end of the Epsilon Eridani Conflicts.

Operation: ODYSSEY TURBULENCE
In 2431, ONI Section One and Three along with the 105th joined together under NAVSPECWAR Group 105 to conduct covert Counter-Insurgency and Terrorism operations across FLEETCOM Sector One Inner Colonies. The plan revolved around two Shock Troop Regiments deploying to newly colonized systems to prevent safe havens for enemies fleeing from the fallout of the Inner Colony Wars. Within the UNSC, the force became known as the Counter-Terrorism Tracking Force to take an initiative in preventing hostilities from breaking out again. The force focused on nearby systems that were easy to reach since they wanted to act swiftly once inside of the systems. The UNSC Navy and Aerospace Force provided transorbital Intelligence, Surveillance, and Reconnaissance to help the Force pinpoint suspectable spots to further study once they had troops on the ground. The 19th Shock Troops Regiment deployed to the Asimov System while the 26th Shock Troops Regiment arrived at the Anu System by the end of 2431.

Throughout 2432, both Regiments participated in the capture or kill of numerous leaders that declared war against the CAA and UEG. The Force established Covert Compounds to set up close to enemy activity and have a place to store prisoners they detained during raids. Supporting the local CMA forces, the NAVSPECWAR group build target profiles and participated in raids to prevent the enemies from getting anything they wanted. The CTTF in both systems provided options for the UNSC to wipe out threats before the enemy had a chance to move, leading to an increase of missions, personnel, and a broader range of targets to go after. As ONI continued to build networks of sources to feed the Force intel, the action arm spent their time tracking and capturing people to interrogate. Such methods gave the Force actionable intelligence for the 105th and Section Three to launch more raids against the enemies. By 2434, the Force had contributed to deterring 57% of terrorist activity while also preventing such movements from popping up again. However, those who were not captured began fleeing towards the Outer Colonies which slowly became a haven for like-minded people.

The operation then set its scope on 61 Virginis and 61 Urase Majoris system where ONI Section One elements tracked fleeing targets to the systems in search of refuge. By 2436, the 105th rejoined the Counter-Terrorism Tracking Force with two Regimental Combat Teams to assist the CMA with taking down sanctuary camps across the colonies. Due to the desire of the CMA wanting to take the lead in operations, the UNSC conducted its own missions which brought disagreements among commanders in both organizations. Working around politics, the 105th worked with Section One on infiltrating into the sanctuary cities and identifying key leaders to remove. After identifying leaders, capture platoons moved in to take away the leaders which led to the disbandment of many cities where more people fled towards the Outer Colonies. In 2441, the 105th succeded in taking down a number of threats and turning their attention more towards the fringes of Outer Colonies space.

For the rest of the 2440s, the UNSC continued to maintain a presence around the Inner Colonies near Sector One while the 105th and CTTF deployed to systems with the most activity. Reconnaissance Platoons from the deployed Regiments augmented themselves with Section One and deployed to the Outer Colonies where they gathered intelligence on movements of enemies and activities. Most of the platoons that deployed worked in two to three-person teams with ONI counterparts and spent the majority of their time on Non-Official Cover rosters to protect their identities. The rest of the Regiment spent their time cross-training with the CMA and conducting missions. In 2452, the UNSC declared Operation: ODYSSEY TURBULENCE a success and quietly ordered the 105th to focus on deployments to the Outer Colonies.

The Handover and Expansion
With the Outer Colonies expanding, the 105th began preparing to conduct special warfare operations in replacement of the CMA. In 2442, the division joined a pilot program known as Naval Special Warfare Sector One Security Task Force and provided Battalions as the action arm. Both Battalions were supported by personnel from the UNSC Navy. Deploying throughout Operation: ODYSSEY TURBULENCE and other operations, the 105th showcased issues and strengths NAVSPECWAR needed to address. Noting the 105th was slow to respond effectively, the commander ran wargame simulations to speed up their response in an expeditionary vision. The command staff created a 105th Shock Troops Force Design doctrine and outlined major overhauls in training, employment, and tactics. Both officers and enlisted focused on supporting the NAVCOM and NAVSPECWAR mission to ensure the success of each deployment. Throughout the rest of the 40s, the 105th modeled themselves into an agile and lethal fighting force. In 2452, the 105th set a standard for colonial special warfare organization and won several wargame competitions against other colonial Shock Troops Divisions.

In 2454, the division received a growth in their budget from both the Marine Corps and Naval Special Warfare Command. They went to work on building new facilities to support updated technology along with exploring a force expansion. The 105th added three new units from the Special Operations Capable community. The 105th Shock Troops Light Armored Reconnaissance Battalion, 105th Force Reconnaissance/ODST Battalion (SOC), and 105th Space Assault Battalion were activated to support the growing division. The 105th Shock Troops Support Group grew to support the expanding Regiments and recruited more personnel. The 105th showcased their newest units in a wargame simulation by 2457. Along with a force increase, the 105th focused on the Preservation of Family Force protocol within the division to provide families of the 105th support networks, community engagement activities, and opportunities to help the division. Throughout the rest of the 50s, the 105th began working on grappling their new fortune, size, and responsibility of handling the Inner Colonies of FLEETCOM Sector One.

Operation: FREQUENT TUNDRA
Following the end of Operation: ODYSSEY TURBULENCE, ONI Section One and the 105th formed a Special Reconnaissance Project named Juliet-37 Task Group under NAVSPECWAR to conduct covert reconnaissance in the Outer Colonies. The Project's goal was to build better target profiles against Targets of Interest around the Chi Eridani and 68 Eridani system based on the growing number of havens and sanctuary communities propping up. In 2453, Section One recruited reconnaissance platoons from the 105th and combined forces to build covers and trust among the two organizations working together. The teams began deployments to the two systems under the cover of merchants in 2454 and began their year-long missions of gathering intelligence.

Both systems proved to be hotbeds for terrorist activity and J-37TG spent little time waiting as they created profiles for TOI in their assigned systems. Mapping out the networks and building sources allowed the Task Group to understand the operational level of the enemy and its activities. In 2457, Section Two joined the Task Group where they began a program to conduct covert political and economical tampering as well as spreading propaganda. The 105th focused on infiltrating military arms of the organizations to understand their capabilities and conducted sabotage missions while also assisting Section One missions. Demolition and Snatch missions became the norm for the 105th as well where they continued to act covert and often outside of military law. Their findings located other cells throughout Sector One Outer Colonies and Inner Colonies, which led to stopping terrorist attacks on growing colonies. By 2468, the Task Group set their eyes on the Eridanus system where the UNSC and CMA had the least amount of intelligence on.

In 2469, the Task Group began year-long long-range reconnaissance missions throughout the Eridanus system. For the next twelve years, the Task Group built profiles on TOIs, networks, connections between the organizations, and embedded with the local CMA forces. Finding that the terrorist groups infiltrated the CMA throughout the system, the Task Group began covert investigations against compromised units and began tracking their activities. After building and maintaining sources, the Task Group informed the CAA and UNSC of their findings but chose not to act till given a green light. The database within the project became known as the Providence Database among targeting officers and analysts. After receiving a green light from the Task Group Commander, the units began snatch-and-grab missions along with targeted killings to prevent future infiltrations. In 2481, Operation: FREQUENT TUNDRA ended when the 105th Shock Troops Division requested for their reconnaissance platoons to rejoin their original postings and support the Division more.

Operation: SCORCHED SERPENT
NAVCOM declared its first counter-terrorism operation for Sector One in 2473 to combat the growing threats of terrorism along the border of Inner Colony space. The 105th Shock Troops Division became one of the many premier forces from NAVSPECWAR to conduct counter-terrorism missions alongside the UNSC Aerospace Force, Army, Navy, and CMA forces. Conflict rose throughout the 105th learning they were not going to be pushing into the Outer Colonies to put down more serious movements. Receiving intelligence from Section One's Juliet-37 Task Group, the 9th and 19th Shock Troops Regiment deployed while the 105th Space Assault Battalion and 105th Force Reconnaissance/ODST Battalion supported the two Regiments on deployment. With a rise of freighter hijackings and space vessel seizures, the 105th Space Assault Battalion prepared themselves for their first combat deployments.

In 2475 and 2476, the 105th Space Assault Battalion conducted two Visit, Board, Search, and Seizure missions aboard the Summer Tuesday and Running Martian after the UNSC Department of Commercial Shipping reported suspicious activity. ONI and the 105th tracked the situation to learn they had been hijacked by terrorists and heading towards Inner Colony space. Since the 105th Space Assault Battalion often had platoons deploy with a MEU's ODST Special Purpose Force, the 105th Space Assault Battalion Command and Control assisted the MEUs with executing the two raids. Breaching onto the ships and using zero-gravity to their advantage, the platoons took down the hijackers quickly, secured the hostages, and cleared the rest of the ship to ensure there were no stragglers. Following the success of the two raids, the 105th Space Assault Battalion became one of the renowned units for combatting terrorism aboard ships and in zero-gravity situations.

Throughout the rest of the decade, the 105th Force Reconnaissance/ODST Battalion conducted several operations under NAVSPECWAR from close-target reconnaissance to direct action missions. Since the battalion also deployed in the ODST Special Purpose Forces of a MEU, elements became notorious among the Navy and Marine Corps due to their ties with the 105th Shock Troops Division. In 2479, the Battalion rose to fame during a 38-hour firefight against a terrorist compound while being cut off from friendly forces for over 18 hours. As a result of the long firefight, many people across the UNSC Armed Forces found the 105th Shock Troops Division rising to fame for carrying out some of the hardest battles and operations for NAVSPECWAR in Sector One.

From 2480 to 2483, the four Regiments of the 105th rotated through the Outer Colonies to carry out direct action missions in the Theta Ursae Majoris and Chi Eridani system. Utilizing actionable intelligence from J-37TG, the Regiments were able to conduct effective missions alongside other ODSTs and ONI Paramilitary Units. NAVSPECWAR designated the units under Task Force 717 where they were able to carry out both covert and clandestine operations in support of the UNSC agenda. As more targets fled to the Eridanus system, the 105th Space Assault Battalion intercepted the fleeing vessels and arrested the individuals on-board. But NAVSPECWAR was not yet ready to push into the Eridanus system despite the overwhelming evidence gathered from ONI and the 105th. By 2483, the UNSC and NAVSPECWAR called the end of Operation: SCORCHED SERPENT and claimed the counter-terrorism operation a success. However, they failed to realize that a much larger threat was growing on the horizon that they could've dealt with during SCORCHED SERPENT.

Insurrection
In 2492, following the bombing of Far Isles, the 105th Shock Troops Division forward deployed the 26th Shock Troops Regiment in preparation to intercept any terrorists that attempted to attack the Inner Colonies. NAVSPECWAR designated a Task Force named the Counter-Secessionist Operations Task Force on Reach to capture or kill leaders of secessionist movements. The 19th Shock Troops Regiment deployed onto Reach to investigate the People's Occupation alongside ONI Section One as part of the Task Force. Not long after, the 105th Light Armored Reconnaissance Battalion saw action against the People's Occupation near Szolnok and decimated the cell where they killed 17 and captured 32 total terrorists. The UNSC supported what NAVSPECWAR was doing on Reach and prepared to replicate the same actions in the Outer Colonies where secessionist movements were rampant. While the UNSC prepared for their invasion of the Eridanus System, the 105th Shock Troops Division prepared to bring back Expeditionary Targeting Forces alongside ONI Section One to swiftly take down the movements in 2493.

UNICOM and NAVCOM launched a joint-operation to combat the secessionist movement in the Outer Colonies. The 105th Regiments deployed with NAVSPECWAR to the Eridanus system to conduct ground special warfare operations while the 105th Space Assault and Marine Force Reconnaissance/ODST Battalion deployed to support VBSS and supply line protection for the logistic elements. The UNSC established Sector One - New Constantinople (Forward) where the 105th Shock Troops Division forward-deployed one Battalion of Shock Troops to serve as a Commander's Crisis Response Unit to respond to a threat. Due to the CMA being unreliable after being infiltrated by secessionist spies, the 105th began building relationships with conventional Marine and Army units to serve as support for missions. Building their relationship with ONI Section One more, the 105th augmented select units to conduct covert operations in support of NAVSPECWAR.

Throughout the final years of the 25th century, the 105th performed several capture-or-kill missions against the secessionist movements where they dismantled cells throughout Eridanus II. With help from ONI Section One, the 105th had access to an unblinking eye on secessionist movement and were able to launch missions against targets and their network. Many of the 105th deployed alongside Marine fixed-wing squadrons and Armored Units to swarm targets quickly with overwhelming firepower and the element of surprise. Utilizing Marine Corps elements made many of the 105th personnel feel better since they were working with people who went through the same training basic qualification training as them. In the wake of the 26th century, the 105th performed over 500 special operation missions since they entered into the Insurrection.

In a UNSC HIGHCOM report, the 105th Shock Troops Division was one of the most deployed units in the Insurrection campaign. Relationships with the conventional troops drove more to try out for the Division and allowed for more in-house operations in the Marine Corps. The Division continued to conduct special operation missions against Insurrectionists on Eridanus II and Mamore. Following a nuclear bombing on Mamore at a Haven arcology that claimed over two million lives, the Division set their sights on the Freedom and Liberation Party using joint ODST/ONI Hunter-Killer Teams to track down those responsible and ensure the dismantling of the party. During visits from senior political and military leaders, the 105th served as personal security details to ensure the safety of each individual who toured a hostile planet in Sector One.

After the declaration of Operation: TREBUCHET, the UNSC supplied more assets to the hunt against Secessionist movements and secretly enabled the 105th to conduct more operations across the colonies. The 105th saw a spike of 150% in their operational tempo and began delivering anybody with Insurrectionist ties to ONI. Assigned under the Combined Forces Command Special Warfare Component Command for both Eridanus II and Mamore, the 105th deployed Regimental Combat Teams to enable their units to conduct missions quicker and efficiently. At one point, the 105th set up their detention facility to conduct interrogations and gather actionable intelligence against targets. The 105th continued to push up against the Secessionist movements and destroyed cells as they began locating top officers and leaders in the United Rebel Front and FaLP.

Following a bombing on Tribute in 2524, the 9th Shock Troops Regiment deployed to support ONI in locating the terrorist cell and taking down anyone who supported the attack. The 105th Space Assault Battalion assisted in the investigation of the National Holiday cleanup in the same year and increased its efforts of VBSS operations. Following the end of Operation: TALON, the UNSC declared the Insurrection dead on Eridanus II and the 105th began returning to Reach in preparation for their next mission plans against Mamore. However, another conflict broke out in the Outer Colonies of Sector Two which led HIGHCOM to order the 105th Shock Troops Division to prepare for deployment to Harvest.

During the Human-Covenant War, an ONI and ODST unit deployed as military liaisons to negotiate terms of ceasefire due to the war. The 105th served as protective security details for the ONI officers and withdrew from combatting Insurrectionists by 2529. As the worlds that held secessionist movements and members fled to the Inner Colonies, the division worked closely with ONI teams to snatch up and prevent any secessionist movement from breaking out during the Human-Covenant War.

Human-Covenant War
In 2525, the UNSC came in contact with the Covenant on Harvest, and the 105th Shock Troops Division was ordered by Sector One Command to prepare for a Sector Two deployment. The Division cited their inability to respond quickly to the threat since they were focused on Sector One Outer Colonies and needed to focus on the Insurrection. Meeting with ONI officers throughout 2525, the 105th learned about the Covenant and fall of Harvest. Planners and Operations Officers began working on ways to put ODSTs into the fight and contain the threat. Three Operations Officers created the 105th Fleet Marines Special Warfare Expeditionary Warfighting Doctrine in late 2525 as a means to augment ODST Companies and Battalions into Marine Expeditionary Units, Marine Expeditionary Brigades, and support Marine Expeditionary Force missions. The Commander of the 105th pushed for Special Warfare Force Marine Expeditionary Units to support the battle after receiving the warfighting doctrine.

Following the breakout of the Human-Covenant War in Sector Two, the 26th Shock Troops Battalion came into contact with the Covenant in 2528 on Hat Yai and received a 37% casualty rate. Throughout the rest of the decade, the 105th deployed units to support the battle in Sector Two while deploying against Insurrectionist movements in Sector One. With the Covenant opening another front in Sector One at the start of the 2530s, the 105th worked to defend the colonies by deploying Special Warfare Force MEUs. The 9th Shock Troops Battalion was reinforced with A Company of the 9th Shock Troops Support Battalion went Missing in Action in 2531 and was considered the greatest loss in the 105th at the time. The Battalion was quickly replaced with new members and deployed to fight against the Covenant in the Outer Colonies. Elements of the 105th participated in battles against the Covenant in the following fronts: Eridanus II, Fractus Asteroid Belt, Eirene, August II, and, Rampart where they sustained a 68% casualty rate, forcing the 105th to call upon reserve forces. Elements of the 105th assigned to an ODST Special Purpose Force participated in the Metisette Conflict.

By 2536, the ODSTs began working in a joint Section One and Three program known as the Hoplite Program to pair SPARTAN-II program operators with ODSTs to conduct operations against the Covenant. The Prowler Corps worked with the 105th Space Assault Battalion to support Operation: HYPODERMIC and Section One created the Intelligence Expeditionary Force alongside the 105th to investigate and track Covenant movements and attack supply lines. The Division increased recruiting and brought reserve forces to support the fight against the Covenant. Since the 105th remained on Reach and were not able to forward-deploy units to anticipate an invasion, they turned their attention to disrupting supply lines while rotating units through MEUs, MEBs, and MEF deployments.

Throughout the 2540s, elements of the Division participated in the battle of Miridem, Alluvion, Sargasso, Minab, Camber, and Roston. While the operational tempo slowed down, the 105th sought ways to prevent the Covenant from invading the Inner Colonies further. The Division was averaging a 60% casualty rate per battle against the Covenant and were struggling to keep their numbers at full strength, forcing them to recruit law enforcement officers and from colonial militias. Colonies such as Sigma Octanus IV and Reach began fortifying their system defenses while the Division continued expeditionary deployments to Sector Two and Four to support combat operations. The 105th Space Assault Battalion continued to conduct interdiction missions of Covenant supplies but sustained combat casualties on each mission. The 105th Shock Troops Combat Development Center worked with ONI's Watershed Division and Materials Group to create better armor to protect ODSTs against Covenant weaponry. Within the Division itself, there was a sharp increase in Post-Traumatic Stress and suicides which the command brought in UNSC Medical Corps professionals to test and evaluate the ODSTs that were at-risk.

In the final years of the Human-Covenant War, the 105th participated in the Battle of Ariel, Reach, and Tribute. During the Battle of Reach and Tribute, the 105th deployed the entire division to the two planets along with elements to Circumstance. Already stretched thin in the Epsilon Erandi System campaign, the 105th was able to coordinate and mount many offensives against the Covenant. Fighting across the colonies of Reach and Tribute, the 105th sustained a 71% casualty rate by the time Reach fell to the Covenant. An element of the 105th that deployed with the Pillar of Autumn participated in the Battle of Installation 04 where they were wiped out. Another element attached to the 26th Marine Expeditionary Force sustained a 91% casualty rate during the Battle of New Jerusalem. The 105th relocated to England and prepared for the defense of Earth and the Sol system following their new orders from HIGHCOM and the Security Council. Under the Core Worlds Sustained Defense Protocols, the 105th began spreading their forces out to help reinforce the Core Worlds. The 2nd and 9th Shock Troops Regiments remained on Earth while the 19th and 26th forward deployed to Mars and Luna; the Space Assault Battalion deployed to the Jupiter moons while the MFR/ODST coordinated their missions with nearby MEU and MEB units on Earth and Luna.

During the battles throughout the Sol System, the 105th deployed all units in the fight on Earth, Luna, Mars, and Jupiter's moons. There, they engaged the Covenant on all fronts under the Sol Naval Special Warfare Component Command. Elements of the 7th Shock Troops Battalion participated in the Battle of Installation 04 where they were nearly wiped out. Fighting continued throughout the SolCore where the majority of operations took place on Africa, reconnaissance teams worked in the area and averaged a near 85% casualty rate. The Light Armored Reconnaissance Battalion were dominant across Luna as they conducted hit-and-run tactics against Covenant ground vehicles. Following the Battle of Voi, the 105th repositioned themselves around Earth and the remaining colonies to fend off the Covenant invasion. A Special Warfare Command and Control along with two combat teams deployed to assist the Battle of Installation 00, the element sustained a 90% casualty rate. Following the death of the High Prophet of Truth, the UNSC began taking the upper hand against the enemy and won back Sol System.

Following the end of the Human-Covenant War, the 105th was nearly destroyed at an organizational level due to the number of casualties. The Division became the most decorated Shock Troops Division for their actions on the Installations and countless engagements against the Covenant. During an awards ceremony, there were fourteen Colonial Crosses awarded to ODSTs for their actions in the war, only one was able to receive it in-person. Other awards included the Legion of Honor, Navy Cross, and Silver Stars; often being awarded multiple times. The Division Commander wasted no time and began rebuilding the 105th, briefly placing the 26th Shock Troops Regiment on reserve duty while working to rebuild the other three Regiments to full strength. The division and Medical Corps began monitoring the mental and physical health of ODSTs to ensure they did not lose more to suicide.

Rebuilding and Relocation
In the wake of the end of the Human-Covenant War, the 105th launched the Comet Project to rebuild the division. Residing at the Marine Corps Base Camp Pennefather, the division launched continuous training along with assessment and selection cycles. Select reconnaissance teams paired with the Prowler Corps began missions to scout out a new training facility for the division 2553. Another combined Ranger/ODST/ONI unit began searching for the 9th Shock Troops Battalion who went MIA in the early years of the war as well by late 2553. The Division Staff published a new doctrine making the unit become a hybrid force for NAVSPECWAR in the event of their deployments. Meaning units deployed were capable of performing NAVSPECWAR operations assigned to the designated deployed unit, giving the division more opportunities to conduct missions and not be restricted to one unified command. By the end of 2556, the 105th placed the 26th Shock Troops Regiment back on active duty.

Underlying issues in mental health and abuse rose dramatically during the stand-down of the division. Divorce rates and spouse abuse skyrocketed along with depression, PTS, night terrors, insomnia, and suicide. Members who retired from the division formed the 105th Helljumper Association to assist the active-duty ODSTs in rebuilding their lives. New members of the division were constantly harassed by the older members and left before they had a chance to deploy. The command launched an internal investigation to learn 92% of the new members to a Shock Troops Regiment were hazed and went after the ODSTs to encouraged the acts. Other ODSTs who became addicted to drugs and alcohol were thrown out while also being placed into a rehab center. An element of Medical Corps and 105th launched a campaign to assist ODSTs with their mental health, marriages, and anything else on the medical side.

In June of 2554, the Division was given the green light to ship to Tribute and move to their new posting, Marine Corps Base Camp Saipan in Sector One. During the construction of the 105th Headquarters, they cataloged every ODST who was killed in action and became known as the Black Book among the people. Training Facilities, Barracks, and Armories were named after ODSTs who were awarded Colonial Crosses to honor those who rose above the call of duty to allow Humanity to have a fighting chance. By December of 2554, the 105th Shock Troops Division had one fully staffed Shock Troops Regiments ready for deployments on Tribute. The rest of the division settled on Tribute by the end of 2558.

Throughout 2556, the 105th launched the Human-Covenant War Force Analysis Report to help build a better understanding of structuring the force, creating a better understanding of breakdowns within combat operations, and future concepts to enable the fighting force. By the end of the report, the 105th concluded their need to restructure their Shock Troops Company, Platoon and, Combat Team. Notably, they dropped Company Commander to Captain, negated Captain Platoon Commander slots, dropped Platoon Sergeant to Gunnery Sergeant, and moved Combat Team Leader to Staff Sergeant. In training, the 105th declared every individual who was to attend Assessment and Selection needed to be at a Duty Station for at least two years before attempting to join the 105th Shock Troops Division. The report highlighted the struggle for quality Company and Platoon personnel given the high ranks and the intense rank inflation within the 105th.

Operation: INHERENT STANDARD
During Project Comet, the division joined a NAVSPECWAR Colonial Project known as the Colonial Advisory Support Element Force, Sector One. The project was known to augment ODST Shock Troop Battalions, Companies, and select Combat Teams to assist corporations in security throughout the Inner and Outer Colonies. The 2nd Shock Troops Regiment supplied units to colonies with multiple conflicts as a means to assist with training, educating, and advising corporate security divisions throughout 2555. The division put together an Expeditionary Intelligence Unit with ONI to conduct reconnaissance, surveillance, and observation missions in the Outer Colonies of Sector One to gather information. Due to the fall of the UEG, the 105th continued to monitor the at-risk colonies and provided non-lethal alternatives to bring them into the Phoenix Initiative.

CASE Force, Sector One became heavily active due to the strong opposition of corporations working in the Outer Colonies. As corporations launched covert campaigns against the people, the CASE Force worked with the local government and corporation to prevent further breakouts. During a meeting between Mamore government representatives and the CASE Force in 2557, a bomb went off and killed both parties. Attacks from both sides were launched in a covert manner and Venezia began descending towards a conflict till the Phoenix Initiative stepped in. The government ordered all CASE Forces out of the Outer Colonies, but the UNSC regional command rebranded the unit as Sector One Augmentation Teams and reinserted forces to track down those who bombed the meeting. The 105th was successful in apprehending the terrorists on Carrow, but their actions strained the relation between Sector One Outer Colonies and the Phoenix Initiative further.

Throughout the 60s, the Sector One Augmentation Team missions were handed off to conventional units as the 105th began turning their attention towards ex-Covenant splinter factions and Insurrectionist activity.

The 105th deployed a force to the Soell System as Technical and Reconnaissance Advisors beside the Concord of Reconciliation. In 2555, elements from the 2nd Shock Troops Regiment, 3rd Shock Troops Battalion participated in a battle against Jiralhanae Loyalists over Alpha Halo. Following the end of the battle, UNSC High Command ordered Sector One to work with the Concord on securing and maintaining security of the Soell System.

In 2556, the 105th stood up a sub-operation known as Operation: INHERENT STANDARD - Comet Shield to assist in locating, targeting, and denying alien operations throughout Sector One. The 105th Space Assault Battalion augmented themselves with civilian and military vessels to conduct counter-piracy missions. A joint ODST and ONI unit formed the Joint Xeno Tracking Force - Sector One to gather information on alien activity and providing plans to take out their positions. The two missions continued on throughout the rest of the decade as the UNSC Navy rebuilt their fleet. During Operation: INHERENT STANDARD - Comet Shield, the 105th ran a joint special warfare operation capabilities exercise to simulate a Covenant invasion of Tribute and ways to effectively respond in 2560.

Operation: HIGH TIDE
The 105th was set to join Operation: HIGH TIDE in 2555. It was known as a UNSC Naval Command operation to deny Covenant remnants strategic locations and installations throughout human space. In Sector One, the Covenant had set up many crucial infrastructures to ensure its success against the UNSC in the Human-Covenant War. In the fallout of the Great Schism, many were left abandoned and Covenant remnants attempted to use them as a means to terrorize the rebuilding UNSC. Following the success of the destruction of the Station of Wise Contemplation in 2554 by a joint UNSC and Concord force, Naval Command up the tempo against other targets. For the 105th, they were green-lit to Find, Fix, and Finish Covenant infrastructure throughout Sector One. They deployed their first forces under various Marine Special Warfare Expeditionary Units alongside the Bravo-9 Division and NAVSPECWAR support personnel. They were assigned to the Mirata Sector as their main Area of Operation Focus.

In the first month of their deployment, the 105th distinguished themselves for destroying mobile Assembly Forges and artificial sliplanes around the Acropolis System. The joint force banded together to use electronic warfare and the Prowler Corps from the Office of Naval Intelligence to infiltrate systems and catch the enemy by surprise. ODSTs were successful in deploying cyberwarfare capabilities to jam and mislead the enemy while they positioned units for assaults. Target Action Teams identified critical infrastructures and locations to attack while ODSTs planned their missions to decimate the enemy positions. Jiralhanae-led Covenant remnants were struggling to maintain a footing in the Acropolis System due to the systematic destruction of their supply and resource lines, forcing them into confrontations with the UNSC. The 105th launched missions to take down the Jiralhanae bases and secure any prisoners who were imprisoned following the Great Schism. Retreating Jiralhanae forces attempted to flee using the artificial sliplanes but found them destroyed which led to the UNSC Navy eliminating what was left of the Jiralhanae forces.

During their operations throughout the Mirata Sector, the 105th deployed NAVCOM Targeting Forces to eliminate the leadership of the warlords in certain locations to destabilize the region. The Targeting Teams included Scout Sniper units and were very successful in conducting their missions. Following the warlord's death, many of the troops aligned under the dead leader would attack each other for leadership while others fled since they lost faith. Other units were forward-deployed to coordinate orbital strikes and take out the command posts to confuse enemy combatants on what orders to follow. Cyberwarfare and Psychological Warfare platoons were deployed to incite prison riots and allow assaulting ODST units to take down the enemy without much trouble. By the end of their first deployment, the 105th was successful in destroying 80% of the essential personnel and equipment in the Acropolis System. Another unit from the 105th was rotated in place and they began their focus on 71 Orions System after clearing out the remaining 20%.

Locating a Beacon used by a Jiralhanae Warlord to supply energy to its Battle Group, the Navy destroyed the Beacon and the ODSTs took on the ground forces on Gaia. Throughout the Battle on Gaia, a 105th Shock Troops Light Armored Reconnaissance Company distinguished themselves in using mechanized special warfare to funnel the retreating Jiralhanae into ODST shock assaults. Wiping out the enemy force, they were able to free prisoners from the Great Schism and locate other enemy forces in the system. While in-system, the UNSC utilized strike force tactics to swiftly deal damage to the Covenant leadership and fracture their ranks. While the warlords dealt with in-fighting of their ranks, the UNSC and Concord were successful in their tactics to destroy what remained of the enemies. With the support of a Concord Battlegroup in 2556, the UNSC was able to destroy the remaining warlord forces and secure the system by late 2557.

By early 2558, the 105th began their hunts against Covenant infrastructure further into the Outer Colonies and worked with the Concord to deny the enemy their chance to utilize Covenant facilities. In 2558, the 105th was rotated off of Operation: HIGH TIDE and continued their efforts through Operation: INHERENT STANDARD and Soell System Patrols. The UNSC recognized their efforts with a Unit Citation for their actions. Due to their capabilities to attack swiftly and violently, the division began preparing for missions outside of the Human Sphere and to hunt Jiralhanae forces in the former Covenant space.

Soell System Patrols
In the wake of the Battle of Alpha Halo in 2555, Sector One NAVCOM forces began patrolling the Soell System with the Concord. The mission became known as Operation: AUTUMN'S REST in honor of the UNSC Pillar of Autumn. Other memorials were dedicated to the 28th Shock Troops Battalion (Reinforced) and the Pillar of Autumn's crew. The 105th began rotating battalions to support the full-time security of the system. The three major forces and their tasks included Study and Analysis, Security, and Training to assist the full-time personnel from the UNSC. Command and Control was placed into the system by Sector One known as Combined Joint Task Force - Soell System and oversaw all UNSC operations in the system. The area became known as Joint Occupation Zone - Soell System and was the first interspecies operation along with the Concord for the 105th Shock Troops Division.

The Study and Analysis Force became well-known for its reconnaissance of Alpha Halo and preparing strategic responses to the arrival of another Halo Ring. Working with personnel from ONI and the Army Rangers, the 105th ran numerous teams around Alpha Halo to help generate combat simulation sequences to help planners study and prepare missions. Security Forces broke into two cells known as Black and Yellow, Black Cell focused on breaking through UNSC bases while Yellow spent their time improving defenses. The Security Forces ran numerous simulations to figure out how to prevent infiltration all the way to full-out assaults they saw during the Battle of Alpha Halo. Notably, the Study and Analysis Force operated missions around Basis to track debris and Flood signatures.

Security and Training were soon handed off to a conventional Marine or Army Division to handle while the Study and Analysis Force continued to operate. The units assisted with conducting Intelligence, Surveillance, and Reconnaissance missions around Threshold to recover any technology. But due to the dangers of Ring fragments, potential Flood outbreaks, and unknown conditions, ISR missions required less boots on the ground. The 105th soon ordered all ODSTs homes after the successful transfer of operations was made to NAVCOM in 2563.

Joint UNSC-Concord Missions
UNSC High Command slotted the 105th to participate in Operation: PALE HORIZON, a joint Concord and UNSC mission to take down Jiralhanae outposts outside of the Human Sphere in 2559. Due to the rise of Jiralhanae splinter factions of the Covenant being close to the Human Sphere, they remained a threat to the UNSC. However, the UNSC was unable to reach the designated targets in time and looked to the Concord as a means of transportation. With the Concord's support, the 105th was able to assign a Marine Special Warfare Expeditionary Unit to the operation. The 20th Shock Troops Battalion with elements from the 105th Shock Troops Special Missions Detachment began an intense work-up to hit a target known as Narske. It was a former Covenant colony used as a military forward operations base in the Human-Covenant War. Deploying after the work-up the 105th began its first out-of-system operation.

Arriving at Narske, the ODST Force launched surgical shock infantry raids on covenant remnants and provide force reconnaissance alongside Concord Special Operations Units. Other missions included zero-g, base security, and training exercises. ODSTs were cited for carrying out significant raids against the enemy forces and providing precise quick reaction forces. The joint-military deployment slowly built trust between the two factions and provided insightful information to the UNSC. Reconnaissance teams conducted black operation missions to record and document the alien system to give planners in the Sol System strategies to attack outside of the Human Sphere. Joint missions between the two remained tense due to the Human-Covenant War and the ODSTs were sure to not align themselves with the Concord. Returning to the Human Sphere in 2560, the 105th was cited for their diligent work alongside the Concord. The ODSTs who were killed in action were recognized by the Concord as a form of respect for humans fighting and dying for their cause. Many veterans and current ODSTs silently protested Concord's decision and asked leadership to get out of the rotation.

The 11th Shock Troops Battalion, along with elements of the 105th Shock Troops Light-Armored Reconnaissance and 105th Space Assault Battalion, rotated into an MSOEU and prepared a deployment to the Rings of Nepharal. The ODST Force was able to improve upon the previous deployment by launching vehicle force reconnaissance and maneuverable special warfare operations to trap covenant remnants. Space Assault was able to showcase their ability to board spacecraft and secure them quickly. The three units were capable of providing more intelligence to planners back in the Human Sphere as well as in-depth analysis of tactics and communications. Despite the upbeat operational tempo, the unit was sent back early due to casualties. The Division launched their own investigation into the matters and requested to be taken off of Operation: PALE HORIZON until further notice. Once the report reached UNSC High Command, the 105th Shock Troops Division was taken off of Operation: PALE HORIZON and never put back on.

Rumors of the report spread like wildfire through NAVSPECWAR and ultimately led to a classified release to all personnel within the 105th. It cited the lack of importance for ODSTs to die for the Concord mission when the UNSC was still recovering from the Human-Covenant War. The Commanding General cited the Division was not going to fight for the Concord until the UNSC was strong enough to defend themselves again. Other concerns cited the worry of being targeted by another large covenant remnant faction and the inability to properly respond to a Covenant-like invasion. Due to the report, the 105th Shock Troops Division was placed on strengthening Sector One's defense and preparing for a near-peer threat.

Outer Colonies Low-Intensity Conflicts
In preparation for a near peer conflict, the 105th prepared three training exercises known as Operation Comet Shield, Winter Strike, and Black Titan to help with stimulating Covenant invasions and providing examples to the 105th on how to react. Training at the Joint Readiness Training Center and Marine Corps Air Ground Combat Training Center on Tribute, the 105th was able to work with conventional forces to help with creating tactics and plans for the near future. Along with the creation of three training exercises, the 105th deployed to the outer colonies to support low-intensity conflicts. Forces deployed to Carrow and Mamore to support counter-insurgency missions and direct action raids with support from NAVSPECWAR by 2563. ODSTs provided personal security detail and augmented themselves with conventional forces to support the long-term counter-insurgency missions. In 2564, the Commanding General created the 105th Shock Troops 2570 Vision and began preparing the force design.

During 2565, the 105th was successful in dismantling the Freedom and Liberation Party leadership on Mamore. A Shock Troops Company launched a successful direct action raid on a meeting location and were able to arrest many of the major leaders. Due to the intelligence goldmine they came upon, the 105th began rooting out the remainder of the FaLP leadership across Mamore. On Carrow in 2566, a Shock Troops Battalion participated in a Counter-proliferation operation to recover nuclear material and captured the terrorist cell involved with the smuggling operation. An ODST PSD team was recognized for their actions in taking down a person who attempted to assassinate the Governor of Carrow in 2568. By 2569, the 105th Headquarters served as the planet special warfare command and control for all NAVSPECWAR personnel on Carrow. After completing their rotation, the 105th Shock Troops was able to completer their 2570 Vision. After cutting the 105th Shock Troops Special Missions Regiment, the 105th perfected their Special Warfare Marine Expeditionary Units and Brigades to deploy as emergency response forces for NAVSPECWAR.

Throughout the 2570s, the 105th moved to support New Constantinople and Ruthersburg but were recalled in 2577 when word of a growing Covenant splinter faction was preparing to invade the Sol System and UNSC Controlled Space. With the Blooding Years increasing and the Covenant splinter factions looking to fulfill the Prophets, the UNSC were in the scope The 105th responded by raising their threat level and forward deploying forces to intercept the possible Covenant threats. In preparation, the 105th participated in training exercises more often and coordinate with NAVSPECWAR forces on command and control. After meeting with the FLEETCOM and CENTCOM Sector commanding officer, the 105th moved forward in coordinating with SPECWARCOM and UNICOM. In 2579, the 105th was placed at their highest level of threat and prepared for an imminent attack by Covenant splinter factions.

Recruitment
The Division recruits from all branches of the UNSC Armed Forces, but the majority of their candidates come from the UNSC Marine Corps and UNSC Navy. Recruiters for the 105th are both enlisted and officers who can travel and recruit members from other units. The basic requirement is for a candidate to have one rotation with a military unit under their belt along with a basic physical test to ensure they can perform well in assessment and selection. During the process of recruitment, the 105th actively seeks officers and enlisted personnel. Officers at the rank of O-2, O-3, and O-4 are the only three ranks that the division selects from in their candidate pool. Warrant Officers at the rank of W-1, W-2, and W-3 are the only three ranks where Warrant Officers can apply to join the division. Enlisted personnel at the rank of E-3, E-4, E-5, E-6, and E-7 make up the majority of the pool. It is not often to see candidates outside of the candidate pool apply for the 105th unless they receive a medical waiver and go through an extensive physical test to ensure the candidate can perform the tasks.

All personnel of the 105th are required to have previous experience before selecting to try out for the 105th Shock Troops Divisions. Enlisted require the least since they can earn a slot for selection at E-3 after a year and a half in their respective military branch. Officers are required to lead a platoon or company before requesting a slot at selection. Candidates who command a platoon and company are more desired and often pass assessment and selection more. Warrant Officers who were promoted from their enlisted rank while serving in the 105th join the division without requiring a slot at selection. Other Warrant Officers do not need prior experience as a Warrant Officer to be slotted for a position in the Division. Due to many of the non-combatant MOS of the 105th, they are not required to attend the Assessment and Selection for the infantry roles. They instead attend a Shock Troops Support Assessment and Selection to determine if they're capable of being a member in the 105th Shock Troops Division.

Support Recruitment
Support within the 105th comes from all over the UNSC Marine Corps and UNSC Armed Forces. Primarily, support personnel from within the UNSC Marine Corps must attend the Shock Troops Support Assessment and Selection Program to serve in the 105th. Support personnel have a variety of options to select from and often choose their duty prior to attending Assessment and Selection. Ranging from Field to Headquarters Status, individuals have the power to choose the way they want to spend their time in the Division. The 105th draws from over forty Occupational Fields ranging from Intelligence to Financial Management to ensure the day-to-day operations of the Division run smoothly. After completing the Shock Troops Support Assessment and Selection, the individual is slotted for a tour then has the option to extend or return to their previous assignment.

Liaison Officers became an internal aspect to the 105th as they modernized and adapted to the ever-changing environments. Liaison Officer tours are offered to every other branch in the UNSC Armed Forces at Enlisted, Warrant Officer, and Commissioned Officer. Individuals who become a Liaison Officer serve in the Operations Company of the 105th Shock Troops Division as Subject Matter Experts on Air Assault, Aerospace Operations, and other Multi-Domain Warfare Platforms. Tours as a Liaison Officer last for four years to allow for the LNO to build an understanding of how the Division operates, build rapport with the Division's Staff, and share their knowledge. Given the select amount of spots for an LNO tour, there are a total of twelve spots, three for enlisted, warrant officer, and officer. Most LNO's tend to be from other Special Warfare organizations to help with joint operations.

Assessment and Selection
The Assessment and Selection program, better known as Selection among the training cadre, is a three-week-long program that looks for the right candidates. The first phase is known as the physical test that looks at the candidate's physical strength, toughness, and ability to perform combat maneuvers. Only getting four hours of sleep, candidates are pushed to their limits so that the cadre can see the true characters of each candidate being assessed. The physical week is the one section where many candidates washout and voluntarily withdraw; it has been noted for being one of the hardest weeks among training cadres in the UNSC Marine Corps. The physical week also serves as a baseline for each candidate, telling the cadre where the candidate is not strong and looking for ways to improve it soon.

The second phase is known as the academic, which is a week-long section focused on the candidate's intelligence, mental resolve, and critical thinking skills. From classroom lectures to psychology exams, the medical staff of the cadre is looking to see if candidates can think during a high-stress situation and command fellow troops. The physical intensity is dialed down to let the candidates focus more on their academics, but wants to keep the body weak to ensure the medical staff can make an accurate assessment. After an academic week, the final week includes an oral board and a final physical test to determine if the candidate should be in the 105th Shock Troops Division. Interviews are held by the senior and command staff of the cadre to determine the true fate of the candidate. After passing Selection, candidates move onto ODST Qualification Training.

ODST Individual Training Course
The 105th Individual Training Course is a three-month-long course focused on developing a candidate's fundamentals in fitness, tactics, combat techniques, and mental toughness. After candidates pass through Selection, the intensity of training is more focused on the mind of the candidate rather than their ability to reach time limits and status quo. The ITC pushes to help develop candidates into capable ODSTs that can conduct a range of missions within a Drop Jet Platoon. In the Fitness Section, the training focuses on hand-eye coordination, teaching candidates to become more endurance, and taking care of their bodies. Medical Officers from the training cadre teach health courses and assist the candidates by employing tactics throughout their training. The Tactics Section educates ODSTs on basic Shock Infantry techniques and developing plans to conduct special operation missions. Members from the 105th and ONI Section One teach ODSTs how to read maps, tell time without watches, navigate areas, create plans in a small team and, execute tasks throughout several environments. Tactics lead right into Combat Techniques, which then helps the candidates stimulate what they learned in tactics and add a combat element. All of the candidates learn field skills such as Survival, Evade, Resistance, Escape, Tactical Combat Casualty Care, Fire Mission Support, and Communication Techniques. The Final Section, known as Mental Toughness, runs the candidates through a test to see if the candidate can perform the tasks they have learned throughout the ITC. Often put against the training cadre, the candidate is forced to use all of the knowledge he accumulated in three months to pass through the final test. After passing the ITC, the candidate becomes an ODST and earns a spot at the ODST Troop Training Phases to join a Drop Jet Platoon.

Phase One
Known as the Small-Unit Tactics Phase, the two sections focus on fireteam and combat team tactics with candidates to determine how they work together. The first section consists of fireteam exercises where the candidates learn how to conduct missions in a small team of four personnel. Emphasis is placed on building trust and respect among those in the fireteam to execute complex special operation tasks under stressful scenarios. The Fireteam section includes live-round exercises such as room clearing, maneuvering on targets across various geographical lands, and honing skills as a team. Other exercises include the usage of tactical training rounds to stimulate fireteam battles better with the help of the 105th ODST Combat Training Unit. The three-week-long section builds into the combat team section which brings in another fireteam to build trust and comradery with other ODST candidates. The combat team section lasts another three-weeks and ends with the new combat team preparing for Phase Two.

Phase Two
The Platoon and Company phase of ODST Troop Training allows candidates to train within an ODST Drop Jet Platoon; candidates continue to perform stimulated special operation missions with the platoon. The Platoon section of ODST Troop Training is the first time ODST candidates can interact with active-duty members of the division. The two-week training period gives time to the platoon to assess and educate the new candidates on how to employ their training. Following the end of the Platoon section, new candidates have joined the 105th Shock Troops Division and prepare for the Company Section. By the Company Section, the five platoons are working together to stimulate combat operations along with doing work-ups for the next deployment. Company exercises include stimulated shock infantry maneuvers, conducting missions with various elements, and using critical thinking to produce effective plans in a short amount of time.

Phase Three
Battalion and Regiment training come in last, they are considered the last Phase for a newly-minted ODST before deployment. The Battalion section focuses on four companies working together to conduct special warfare operations for the UNSC Marine Corps. Battalion troop training includes wargaming against other battalions within the division and, participating in joint capability exercises with the UNSC Army. Battalion training is often done with a variety of units within the Division to keep ODST skills sharp. The Regimental Section is the last and final section of ODST Troop Training, which focuses on a full deployment of a Regiment. Training largely reflects what's done during the Battalion section but heavily focused on the geographical terrain as to where the Regiment is deploying. The Regimental Section is conducted one-week till deployment and ensures that all ODSTs are prepared for their deployment.

Advanced Training
The 105th Shock Troops Division encourages ODSTs to continue attending courses and schools to become better fighters and thinkers for the Division. Many ODSTs attend schools within their assigned MOS to become more skilled and specialized while others build themselves up as well-rounded service members. The Marine Corps Forces Special Warfare Command holds several courses and schools to give ODSTs a variety of options to choose from, such as advanced special reconnaissance, master breacher, assaulting, and advanced driving courses. The UNSC Aerospace Force often trains ODSTs in combat medicine, conducts Search and Rescue Capability Exercises, qualifies Joint-Terminal Attack Controllers, and simulates transorbital operations for Space Assault Battalions. ODSTs often attend SERE Courses through the Aerospace Force due to their dedicated SERE's program. The UNSC Army offers a host of schools that range from Reconnaissance and Surveillance Leaders Course, Ranger School, Long-Range Target Interdiction, Advanced Reconnaissance, Target Analysis, and Exploitation Technique Course. The UNSC Army often assists with providing crucial special operations educations to ODSTs to ensure they have a strong background in their field of expertise. The UNSC Naval Special Warfare Command provides a wide range of maritime, EVA, individual skills development, and vessel boarding techniques such as the Naval Special Warfare Sniper School, Advanced EVA tactics, and close-quarters battle aboard ships.

The Office of Naval Intelligence Section One assists with training ODSTs in intelligence and target identification along with helping select ODSTs become case officers. Section One also assists in teaching ODSTs how to operate undercover and ways to produce actionable intelligence, giving students the best chances to gather the best information for fellow ODSTs in their company. Officers who attend Section One courses can often serve as liaison officers later in their career and become spy handlers within the Division during deployments. The Targeting School allows for officers to become qualified targeting officers and analysts, many ODSTs serving in reconnaissance or intelligence positions attend Targeting School. Section One courses and schools are considered the most elite where veteran ODSTs attend after spending several years in the Division.

Culture
Known as one of the best fighting forces in the UNSC Armed Forces, the 105th Shock Troops Division is known for its aggressiveness and intense focus to conduct combat missions. Since the 105th has predominantly operated in the colonies, the unit was the center of attention for controversies that involved the treatment of prisoners, suspectable war crimes, and scandals within the unit. Many historians looked at the history of the 105th and other units, finding they were the same issues among many Marine Divisions. The only difference was that the 105th received more fame since they were located on Reach. Many senior officers and enlisted personnel claimed the division to also be HIGHCOM's unit, which later proved to be false. Then, the critics shifted to ONI since the 105th worked much more closely with Section One and Three during the Human-Covenant War.

ODSTs inside of the 105th wanted to be there since they knew they were going to get the big missions in Sector One. All of the units inside of the Division have been recognized for their success in battle, most notably the Shock Troops Regiments and the Space Assault Battalion. At first, the division was known as an overflowing fraternity house where ODSTs showed off to their peers how good they were. The Command took a strong-arm approach to the perception and taught their ODSTs on the importance of being silent professionals and seeking no recognition for their work. To support the newly found perception, any ODST from the 105th who spoke about his service to gain a profit was labeled persona-non-grata and not allowed to attend any reunion events. Following the end of the Human-Covenant War, the command created The Black Book to remember all those that had lost their lives while serving in the Division.

Officers who progress their career within the division, often go on to serve in some of the most notable Special Operation Commands there are in the UNSC. An overwhelming amount of officers are often slotted to serve in liaison command positions within their assigned Sector, NAVSPECWAR, and ONI due to their knowledge of working joint operations. Enlisted personnel who stay inside of the Division for their career are known for being some of the smartest ODSTs due to their pursuit of academic knowledge mixed with an operational background on colonial conflicts. The relationship between the enlisted and officers remained extremely relaxed throughout its time, emphasizing a decentralized command and having trust in those on the ground.

Retired personnel from the 105th are often invited to reunion parties to remember their time in the division, they are often coordinated by the training class graduate year. The 105th Shock Troops Hall of Fame was created following the Inner Colony Wars to commemorate individuals who served a successful career in the 105th. Veterans of the 105th have formed numerous support networks to help active-duty ODST families and individuals throughout their time in the division. The most notable is the 105th Helljumper Foundation which works closely with the division to provide community assistance.

Stations

 * Marine Corps Base Camp Nassau (Reach, Epsilon Erandi System, Kepler Sector, Sector 1), 12 May 2370 to 5 September 2552
 * Marine Corps Base Camp Pennefather (Earth, Sol System, SolCore), 13 September 2552 to 23 June 2554
 * Marine Corps Base Camp Saipan (Tribute, Epsilon Erandi System, Kepler Sector, Sector 1), 24 June 2554 to Present