Defeated the Preacher.

The player has become a Big Daddy

The player has successfully hacked a turret

The player has fully upgraded two weapons

The player has fully upgraded one weapon

The player has successfully invented at least one item

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

Confronted Lamb's lieutenant in Pauper's Drop.

Researched a Splicer with the Research Camera.

Defended yourself against the Big Sister without dying.

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.