The multiplayer component of BioShock 2 was developed by the London, Ontario–based game developer Digital Extremes.

In four of the five modes—which are otherwise typical multiplayer games—there’s an unusual wild card. A Big Daddy suit is randomly dropped somewhere in the level, and a player who finds it can choose to don the suit. It grants greater strength and endurance, but Big Daddies cannot use plasmid attacks.

The real magic of the multiplayer feature, though, is that it adds to the BioShock story. In 1959, a year before the events of the first BioShock, players choose one of six characters, all splicers who have been selected to test weapons and genetic enhancements for Sinclair Solutions. The combat takes place during the civil war that Frank Fontaine and Andrew Ryan brought to Rapture, and acts as an interesting prologue.