Missile Lock -
To use the Missile Lock, hold the FIRE button after shooting to lock the missile on an enemy.

Super Weapons -
While playing quickly press Up, Down, Left, Right, Triangle, X, Square.

Weapon energy Power-Up/Max out! -
Pause the game then hold L2 and press Up, Down, Left, Right, Triangle, X, Square. Unpause the game while continuing to hold L2. Your Weapons should be at the maximum level.

Hidden/Bonus Characters -
At the Options screen, hold R1+R2+L1+L2 and press Circle, X, Triangle, Circle, Circle, X, Square.

GameShark / Pro Action Replay / Xploder and Xplorer Codes:

Infinite Health P1 -- 800d9b1a00a8
Infinite Health P2 -- 800d9b1c00a8
Infinite Specials P1 -- 800d9b220004
Infinite Specials P2 -- 800d9b240004

1 Hit Kills P1 -- d00d9b1a00a8 -- 800d9b1a0001
1 Hit Kills P2 -- d00d9b1c00a8 -- 800d9b1c0001
No Specials P1 -- 800d9b220000
No Specials P2 -- 800d9b240000

Sudden Death Mode
d00d9ae00014 -- 800d9b220000 -- d00d9ae00014 -- 800d9b220000
d00d9ae00014 -- 800d9b1a0001 -- d00d9ae00014 -- 800d9b1c0001

Start Button For Health Restore -- d00d4e3c0020 -- 800d33dc1518
1T Thunder Command -- D00D4E3C ????
1 Infinite Health -- 800D33DC 1518
2 Infinite Energon -- 800D357A 0000
3 Unlock All Missions Set 1
[Push SELECT before starting a game]
D00D4E3C 0040 -- 800B2C14 0100 -- D00D4E3C 0040 -- 800B2C18 0005 -- D00D4E3C 0040
800B2C20 0100 -- D00D4E3C 0040 -- 800B2C24 0005 -- D00D4E3C 0040 -- 800B2C2A 0005