![4girls alien animal_helmet artist_name big_sister bioshock bioshock_2 black_bodysuit bodysuit bow cake celty_sturluson combine_assassin creamer_(vessel) crossover cup diving_helmet drinking_straw durarara!! failure food girl_sandwich half-life half-life_2 helmet jesscookie mass_effect multiple_crossover multiple_girls one-eyed quarian sandwiched tali'zorah tea_party teacup teapot tiered_tray trait_connection zipper rating:s score:5 4girls alien animal_helmet artist_name big_sister bioshock bioshock_2 black_bodysuit bodysuit bow cake celty_sturluson combine_assassin creamer_(vessel) crossover cup diving_helmet drinking_straw durarara!! failure food girl_sandwich half-life half-life_2 helmet jesscookie mass_effect multiple_crossover multiple_girls one-eyed quarian sandwiched tali'zorah tea_party teacup teapot tiered_tray trait_connection zipper](/cdn_image/preview/d8/8a/d88a381f298b31cc8752a800764d3966.jpg)
In BioShock 2, the Big Sisters are post-pubescent Little Sisters that have become unstable in Rapture's environment. Ten years after the events of BioShock, they are charged with maintaining the ecological balance in Rapture. The Big Sisters' designs are geared towards accommodating Little Sisters; they have a cage-like basket that is adorned with ribbons, which is used to safely carry Little Sisters on their backs, and childish doodles can be seen on their oxygen tanks.