Finish the game with a time between 3:31 and 5:00 for an A rank to receive the Submachine Gun and Leech Hunter mini-game.

Finish the game with a time of 3:30 or faster for an S rank to receive the Rocket Launcher, Submachine gun, and Leech Hunter mini-game.

This must all be done on normal difficulty. You will not get the ranks if you get finish the game under easy difficulty.

Get one hit kills:
As Rebecca or Billy and you get bit by a zombie, move the character opposite of your main character directly behind the one you are controlling to have him or her shoot the zombie in the head and kill it in one hit, while the zombie deals you no damage. Note: You must have pistol equipped to save ammunition for a one bullet kill.

Extra inventory slot:
When playing as Billy with Rebecca as the alternate character, have Billy hold all the pistol ammunition for both characters and keep her gun fully loaded. This gives you one free inventory slot.

Get alternate costumes:
Finish the game with any rank under normal or hard difficulty. Begin a new game. The Closet Key will appear in your inventory. Use it to receive the closet in the room where the Hunting Gun was first found to access new costumes for Rebecca and Billy.
Get completion bonuses:
Finish the game with a B, C, or D rank to receive the Leech Hunter mini-game.

Dail door number puzzle:
Submit the code 4863 on Disc 2, where the cable car is located.

Brake system puzzle:
The main code is 9 + 9 + 9 + 9 + 9 + 9 + 9 + 9 + 7 + 2 = 81, It will enable the brakes for the train.

Fountain circle puzzle:
Upon arriving at the fountain circle with the six animal statues on Disc 1, use Billy to light the statues in the following order: Deer, Wolf, Horse, Lion, Snake, Eagle.