Twisted Metal: Head-On - Cheat mode

Killer weapons:
Press X2, Up2, L R during game play.

Invincibility:
Press Right, Left, Down, Up, L R during game play.

Infinite weapons:
Press Triangle2, Down2, L R during game play.

Mega guns:
Press X, Triangle, X, Triangle, L R during game play.

Health for weapons:
Press Triangle, X, Square, Circle, L R during game play.

Temporary shield:
Press Right2, Down2 during game play. If done correctly, your car will glow green for a few seconds.

Temporary invisibility:
Press Left2, Down2. Note: This uses up about one quarter of your energy.

Spawn a mine:
Press Right, Left, Down, Up during game play. If done correctly, a blinking red mine will appear underneath your car.

Spawn a freeze missile:
Press Right, Left, Up, Down during game play to create a freeze missile. When this touches an enemy, it will freeze them for a few seconds.

Unlocked primed:
Press Up, X, Up, X, L R during game play. A message will confirm correct code entry. Note: Do this in story mode after using up all weapons.

Play as Axel:
Successfully complete the Russia mini-game in story mode.

Play as Cousin Eddy and ATV:
Successfully complete the L.A./Cousin Eddy mini-game in story mode. [Screenshot 1] [Screenshot 2]

Play as Crimson Fury:
Successfully complete the Monaco mini-game in story mode.

Play as Dark Tooth:
Successfully complete story mode in single player mode.

Play as Hammerhead:
Successfully complete the Tokyo Rooftop mini-game in story mode.

Play as Mr. Slam:
Successfully complete the L.A. mini-game in story mode.

Play as Tower Tooth:
Successfully complete the game in story mode with any five characters. Note: Tower Tooth can only be played in the Rome Deathmatch level.

Greece Deathmatch level:
Successfully complete the Greece mini-game.

Egypt Deathmatch level:
Successfully complete the Egypt mini-game.

Paris Deathmatch level:
Successfully complete the Paris mini-game.

Rome Deathmatch level:
Successfully complete the Rome mini-game.

Tokyo Streets Deathmatch level:
Complete the Tokyo Streets mini-game.

Tower Tooth Challenge level:
Successfully complete the game with any four characters. The Tower Tooth Challenge level will now be unlocked in challenge mode.