Battle of Dyrssen

Commodore Andrea Hopper commanding Battlegroup Constellation, containing the Devana-class ships, UNSC Constellation, Kentucky Rifle, Insufferable, Right Between the Eyes, and 6 destroyers successfully ambushes and destroys the Covenant ORS-class Heavy Cruiser Purity of Judgement under the command of Shipmaster Letho ’Utermee. The Purity had been detached from the main Covenant fleet and had begun an intense campaign of commerce raiding against human freighters, both civilian and military. Data gained from the battle would further refine the refits of other Devana-class ships. Post-battle analysis would also help prove that the Covenant has faster-than-light sensors due to the Purity of Judgement reacting to the battlegroup's entrance before the light of their slipspace portals could've reached the ship.

Prelude
During his raids ‘Utermee would use the navigation logs of several freighters to find and destroy vital refueling and supply depots. Standard convoy escorts would prove insufficient against the ORS and as such heavier units would be needed to deal with it. 3rd Battlecruiser Squadron would be assigned to act as freighters to lure the Purity into an engagement. The squadron would be escorted by Destroyer Squadron 41 and supported by the prowler Moonless Night and the sensor ship Nearsighted. The Devana-class was uncommon and so far, had not been used very often, with many being refitted to modern standards. As such it was unlikely for the Covenant to recognize them as warships, especially with a prowler running interference. 3rd Battlecruiser squadron was the first formation to contain newly refitted Devanas. Replacing 5th Battlecruiser Squadron that had been operating with Cole since the Second Battle of Harvest.

The Dyrssen System was chosen, containing a refueling depot around a fuel-rich gas giant. The depot had been built by the CMA for military operations during the Cold War but had been servicing UNSC vessels since the start of the HCW. Considered at risk by analysts, it was decided to bait the ORS into attacking the system. A courier was placed on the edge of the system so that the UNSC could be alerted when the ORS was attacked. Letho would often loiter in a system for a few days waiting for freighters that had been expecting resupply to come into his waiting arms.

On August 22nd, the courier would arrive at New Tharsis. Alerted, 3rd Battlecruiser Squadron and Destroyer Squadron 41 set off as Battlegroup Constellation, they would arrive in 2 days.

Battle
Entering the Dyrssen system at 07:49, Battlegroup Constellation, would form up into a loose convoy, with the battlecruisers and sensor ship playing the role of freighters and the destroyers escorting. ‘Utermee would be alerted to the battlegroup’s presence within in minutes and would have his ship prepare to ambush the convoy once they entered the gas giant’s sphere of influence. By 09:58, the battlegroup had spent two hours in the system without detecting the ORS and were now passing though the giant’s L2 point. Hopper decided to contact the sensor satellites that had been placed around the gas giant in the hopes of picking out the ORS. The Purity of Judgement would pick this up, and now that the battlegroup was closer ‘Utermee had a suspicion that something was different. Seemingly confirmed minutes later when the sensor ship Nearsighted began actively scanning, passing over the Purity several times. ‘Utermee would send a message to Imperial Admiral Xytan that he was engaging an enemy force, and then made a mircojump to the L2 point.

The Purity of Judgement would exit slipspace 200,000 km off the convoy’s lead ship. With little time to react, the convoy broke up, hoping to force the Purity of Judgement to divide its fire. ‘Utermee who had not fully grasped what kind of trap he was walking into, targeted the destroyer escorts and sensor ship with his initial barrage. The Nearsighted was destroyed almost immediately and lost with all hands. The destroyers Jovian Moons and Homeric Epic were also disabled with this salvo. At this point all four of the battlecruisers had turned their MACs on the ORS, firing in unison, the salvo would nearly drain the shields. Had the ORS been of lighter tonnage then it would’ve been ripped apart by such a barrage.

‘Utermee now recognizing the threat posed by the supposed freighters turned his attention to them as they began to move evasively. The UNSC Right Between the Eyes would be the first to take a hit, with the ORS’s heavy plasma lance creating large gash amidship before penetrating though the ship. Plasma torpedoes would soon follow crippling the ship. The ship would then lose control and begin to tumble before losing power. Before he could fully destroy the ship the destroyer UNSC Tyre and battlecruiser Insufferable would fire their MACs and missiles to little effect. Although it did draw attention away from the stricken battlecruiser. Firing one the lighter Felo-pattern plasma beams, the beam would strike one of the Archer missile magazines, detonating several missiles and causing a massive explosion on her starboard side. The Insufferable would pull back with the Tyre doing her best to cover the larger ship.

Maneuvering towards the ORS’ dorsal side Constellation and Kentucky Rifle along with the destroyers UNSC Sagamore, Spring Awakening, and Patroclus, would allow fire a salvo from their MACs, concentrating fire on the ship’s dorsal side. At this point with her shields nearly drained, the salvo would finally cause damage to the ORS’ hull. With the shot from Kentucky Rifle hitting the neck that connected the bow with the rest of the ship. While not severed, the bow lost power and with it the heavy plasma lance. The follow-up missile barrage was more successful than the one launched by Insufferable and Tyre, if because of numbers if nothing else. While the Archers had little effect, the Bidents would breach the armor cause further damage to the heavy cruiser’s internals. Return fire from the ORS would damage the Kentucky Rifle with a glancing hit from the plasma beam disabling the MAC and damaging the ship’s heat sinks. Forcing her disengagement. Constellation would receive half-a-dozen hits from plasma torpedoes across the bow, though ruining the armor, none would melt fully though.

‘Utermee realizing the battle had turned against him decisively made the decision to retreat and save the valuable Purity of Judgement rather than risk its destruction. Before he could jump to slipspace however, the Purity was rocked by a nuclear detonation as a nuclear-tipped Hyperion missile from the Insufferable hit. ‘Utermee would order one final plasma torpedo barrage and shot from the plasma beam, disabling the Insufferable before she could get a shot off from her MAC.

At this point the Purity of Judgement needed to retreat, she was venting atmosphere in several places, her bow was without power, and the nuke had disabled life support in that section. And fires were spreading throughout her decks. Worse was that despite repeated hails to the main fleet under Xytan, ‘Utermee had remained unanswered. As such without the hope for reinforcements, ‘Utermee needed to leave the field. In his haste however, he rushed the targeting solution on the Constellation and what had meant to be a concentrated torpedo barrage that would’ve disabled the ship’s main gun had been to spread out to properly melt though the armor. Constellation’s shot though the Purity’s engine section would see her float dead in space.

With retreat now impossible, and furthering combat impossible for his ship, ‘Utermee ordered the Purity of Judgment scuttled. Most of the crew would be forced to go down with the ship. However, a handful of menial Unggoy and Kig-Yar would reach escape pods which would later be picked by the remaining UNSC forces. Finally, at 12:23, the Purity of Judgement would scuttle by breaking the safeties on the reactor and causing an unregulated fusion reaction. Only 54 of her 1250 strong crew would survive; all would be captured by the UNSC.