Key

The two different Keys from Wolfenstein 3D.

The two different Keys from the mission packs.

Keys are items found in Wolfenstein 3D that, once picked up, enable the player to open locked doors. There are two colored keys: gold and silver. Once a key is picked up, it is shown in the player's HUD and may be used to open any number of locked doors, but only ones that correspond to the type of key picked up.

Trivia

• All enemies can open locked doors just as easily as unlocked doors. Thus, even if you don't have a key, by shooting a gun or otherwise alarming a Guard on the other side of a locked door, you can theoretically lure him to open the door, possibly even saving time in a level.

Be cautious, though, that you don't let the door close while you're on the other side if you intend to come back. You'll be trapped, unless you can find a Key or get another enemy to open the door. To avoid this situation, kill the enemy while he stands in the open door - it'll never close.

• The two keys in the game are known in the source code as "bo_key1" and "bo_key2". Oddly, the source code also refers to a "bo_key3" and "bo_key4" which are never otherwise seen or mentioned. It's possible that these are the remnants of additional keys originally planned for development.