Opis: The objective of this game is to collect all of the keys to activate the exit, and then make it safely to the exit to advance to the next puzzle/level. You will also find keycards that open locked doors, though some keycards are single use, which means you will need a keycard each time through; while others remain unlocked once you have the keycard. There are other subtle differences between items that you get acquainted with as you go.