S.T.A.L.K.E.R.: Shadow of Chernobyl Cheats

To sneak into the armory, push a chair from the other room to the guard. It doesn't matter if the chair falls down partway. When it is touching the guard, jump on it, then jump onto him. The game will push you past him, into the armory hallway. To access it, simply slash the lock with your knife. To get out, use another chair in the armory or the other room.