Trap Door is a game that came out in the mid-80's for the Commodore and other computers of the time. I would classify the game as more of an "adventure" game than an action game, because the core of the gameplay consists of solving puzzles by making use of objects lying around. There really isn't much action. You take control of Berk, a rotund blue monster of some kind. As I kid playing this game, I always thought this was a game about the Cookie Monster from Sesame Street. The goal of the game is to perform tasks for a never-seen entity who lives in the upper floors of the castle. That's where the puzzles come in. In order to complete these puzzles, Berk sometimes needs the help of creatures that live under the "trap door". Once the creatures are no longer needed, Berk has to get the creatures back under the door. Trap Door was followed shortly after by a sequel called Through The Trap Door, which was basically the same game.
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