Biohazard 2 Cheats

Unlimited ammunition:
Press Up(2), Down(2), Left, Right, Left, Right, R at the item selection screen. Press Up(2), Down(2), Left, Right, R at the item selection screen in the Japanese version of the game.

Extreme battle mode:
Finish both of either character's scenarios, then go to the "Special" option. A new "Extreme battle mode" selection will be unlocked.

Shotgun or crossbow:
When playing as Leon go to the gun shop with the man. He will almost shoot you. After he dies because of the zombies, kill them. Then go up to the dead man and press Action. You should get a shotgun. If playing as Claire you will get the crossbow.