Uncovered the secret of Dionysus Park.

Defeated the Preacher.

Bought one Plasmid or Tonic Slot at a Gatherer's Garden.

Researched a Splicer with the Research Camera.

Hacked one of each kind of machine.

Adopted a new Little Sister for the first time.

Defended yourself against Lamb's assault in the train station.

Found your way back into the ruins of Rapture.

The player has completed the game without harvesting any Little Sisters

The player has become a Big Daddy

The player has either Harvested or Rescued every possible Little Sister

The player has fully upgraded two weapons

The player has fully upgraded one weapon