First and last of any series (much like children) are always getting more attention than the middle child. Bioshock 2 is the only bioshock with multiplayer. Capture the sister (not lilicon i swear) was a fun game mode especially with spawning as the big daddy. Bioshock 2 is the only one to have you play as a big daddy. This means the powerful harpoon guns and DRILL BUILD. Bioshock 2 also has a good story on its own with its little sister mechanic being applied to the protagonist plot and seeing your little sister become a fearsome big sister.