Deluge

A former Sangheili colony where planetary flooding initiated by an increase in stellar activity and the consequent glacial melting caused most of the inhabitants to abandon the world and its cities, which now lie in ruins. Now there is much trader and pirate activity in the flooded cities, and many Kig-Yar in particular call the place home. The capital city in particular - which now carries the same name as the planet - is a nexus of activity, and a ramshackle of structures has been built on top of the foundations provided by the city. Some of the towers and domes remain partially above the water, and many bridges and pontoon-structures cross between the "islands" created by the partly submerged spires, complemented by the husks of scrapped ships of both the space- and seagoing kind. The planet's original name is Jart, but it has primarily been known as Deluge for several ages.