Kill an enemy by dropping a structure on them.

Collect 256 paint colors.

Open five coin lockers.

Play all non-casino gambling games.

Reach Central Park

Single Player: Kill two enemies with a single bullet

Defend Central Station

Reach the Hargreave-Rasch building

Infiltrate the alien hive

Single Player: Kill at least 3 enemies with a single grenade

Single Player: Kill 4 enemies in a row with headshots

Escape the Battery Park evacuation center