Go to "Game Settings", and enter the following codes to the "Cheat" menu:
Unlock all acts - R2, Right, L2, Up, Square
All "Bonus Features" are now awailable - Left, R1, L1, Down, Circle
Grenade Bullets - X, Circle, Square, L2, R2
Invincibility - Up, Square, Circle, X, Down
Single-shot kills - Circle, L2, Down, R1, X
Unlimited Ammo - L1, L2, X, R2, R1
Unlimited first aid kits:
Type in the Chris Barnes code first in Episode 2, when you have to make
the optical disc. You will get a aid kit. Repeat as many times you want.
Unlock storyboards
Finish the indicated episodes bellow with the character:
20-27 - Finish Episode 1, Act 1 with either character
28-32, 37, 38 - Finish Episode 1, Act 2 with Scully
33-36 - Finish Episode 1, Act 2 with Mulder
39-41 - Finish Episode 2, Act 1 with Mulder
42-55 - Finish Episode 2, Act 2 with Mulder
56-59 - Finish Episode 2, Act 1 with Scully
60-73 - Finish Episode 2, Act 2 with Scully
74-84 - Finish Episode 3, Act 1 with Mulder
85, 86 - Finish Episode 3, Act 1 with Scully
87-100 - Finish Episode 3, Act 2 with Mulder
101-115 - Finish Episode 3, Act 2 with Scully
Note: Storyboards 1-19 are already unlocked at the beginming of the game.
Unlock concept art
Finish the indicated episodes bellow:
Roscoe Zombie, Mandy (x2), Dr. Dawson - Available at begining of the game
Postal Zombie, Hector Zombie - Finish Episode 1 with Mulder
Disciple A-Harvester (2), Disciple C-Pyro - Finish Episode 2 with Scully
Hector Zombie (2), Mutant Wolf - Finish Episode 1 with Scully
Mutant Wolf (2), Disciple A-Harvester - Finish Episode 2 with Mulder
Disciple C-Pyro (2), Disciple D-Pitcher (x2), Mutant Slug - Finish Episode 3 with
Mulder
Constantine Creature, Disciple E & F - Avatar Twin, Constantine (x2) - Finish
Episode 3 with Scully
Unlock video footage:
Finish the indicated episodes bellow:
Frohike - Available at begining of the game
Byers - Finish episode 1 with Scully
Cigarette-Smoking Man - Finish episode 1 with Mulder
Krycek - Finish episode 2 with Mulder
Langly - Finish episode 2 with Scully