- Special attacks
- Freeze: Press Up, Down, Up.Shield: Press Right(2), Down(2).
- Rear Fire: Press Left, Right, Down, L2.
- Drop Mine: Press Right, Left, Down.
- Jump: Press L1 + R1.
- Play as Axel
In the Playground Peril level in tournament mode, shoot a missile at the middle swing on the swing set that is in the background next to the merry-go-round. A small statue of Axel will be thrown into the playing area. Pick that up to unlock Axel.
- Play as Darkside
In the Kitchen level, go to the sink and drive down the plumber's butt. Go onto his leg and napalm his butt. He will blow a hole in the wall. Enter the hole to unlock Darkside.
- Play as Mime
In the Holiday Havoc level in endurance mode, shoot missiles at the Christmas tree until it is destroyed. Get on top of the fireplace then jump off backwards and shoot a missile at the stockings. Destroy all four to reveal the icon that unlocks Mime.
- Play as Trapper
Successfully complete the game with Mime to unlock Trapper as a playable character.
- Shock Therapy level
Kill 10 guys in endurance mode to unlock the Shock Therapy level.
- Buster's Lanes level
Kill 20 guys in endurance mode to unlock the Buster's Lanes level.
- Holiday Havoc level
Kill 30 guys in endurance mode to unlock the Holiday Havoc level.
