At the weapon equip screen, press Up, Up, Down, Down, Left, Right, Left, Right, Aim.
Start a game with either leon or claire on "normal" difficulty. Do NOT pick up any items through the beginning until you get to the police station (this means no ammo, or the shotgun/bowgun). When you get to the outside of the police station, the 2 zombies that were normally are gone. Go down the big stairs right when you enter the outside of the police station, and you should find brad from resident evil 1 as a zombie. He is very hard to kill. Once you do, he will drop a special key. Take it to the dark room, open the locker with it, and there will be new costumes for leon/claire.
Beat the game to unlock an extra difficulty level under arrange and original modes.
Beat the game on the hard difficulty level with the best rank for Claire's A and B scenarios and Leon's A and B scenarios. Hunk is a soldier that must reach the second floor of the police station from the sewer with just battles and no puzzles. Extreme Battle mode unlocks Chris Redfield and Ada Wong as characters.
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