Critical Depth Cheats

Invincibility:
L1, R1, L1, R1, Up, Down, Left, Right

Unlimited Weapons:
L1, R1, L1, R1, Up, Down, Left, Down

Drop Pod:
L1, R1, L1, R1, L1, Up, Down, Left, Up

Quad Damage:
R1, R2, R1, R2, Up, Down, Up, Down

To play as Mr. Phatt:
While fighting Mr. Phatt, finish him off with a combo that does at least 48 points of damage. Once he's unlocked, you can select Mr. Phatt on the Character Selection screen.

To play as Abaddon:
Complete the entire game in Captain difficulty mode. Once he's unlocked, you can select Abaddon on the Character Selection screen.

To play as Agent 326:
Beat the Cephalapods (end of game bosses) with a final score of at least 1,000,000 points.

To play as Overseer:
Beat the game with all of the NON-hidden characters - make sure to save after you win with each guy.

Game Shark Codes

Infinite Health P1		801df15e0073

 
Infinite Magnetic Suckers	801df5ce0900

 
Infinite Neato Torpedoes/ 	801df5d00909
Piranha Swarms

 
Infinite Shaker/		801df5d20909
Pilot Torpedoes

 
Infinite Slow Poke/		801df5d40909
Remote Charges 

 
Play As Abbadon			801d0094000e

 
Play As Agent 326		801d0094000c

 
Play As Mr. Phatt		801d0094000d

 
Play As Overseer		801d0094000f