Mass Effect: Ghosts
The planet Rannoch, an arid planet orbiting an older star in the Tikkun system, is the former Quarian homeworld. Almost three hundred years ago, the Quarians were driven from Rannoch by the Geth, synthetic servants who gained sapience and rebelled against their creators. Although Rannoch is now largely uninhabited, the Geth have acted as caretakers, working to repair the planet’s ecology, restore ancient structures, and cultivate some farmland.
Rannoch has no insect life. As a result, its pollinating plants evolved to rely on animals for propagation. This symbiosis between flora and fauna is responsible for the Quarians’ weakened immune systems, which made colonization of other planets extremely difficult after their exile from Rannoch. For many Quarians, reclaiming their homeworld from the Geth is a matter of both cultural and physiological necessity.