Games often have nonplayer characters (NPC) which are characters that are not controlled by the player. Add an EvilWizard to the castle game. When you first play the game, the Evil Wizard is in the Courtyard, and his description says that he is in the Courtyard, but then disappears. Every other time after the first time you enter the Courtyard, the Evil Wizard does not appear in the description. But if you visit theWizard’s Room, the EvilWizard can be found there. You defeat him and win the game.