Warp door (Wario: Master of Disguise)
From the Super Mario Wiki
In order for it to appear, Wario must draw a large square with a line going through it, making the door appear. On top of the warp door is a pumpkin-like statue that is shown to be alive. The warp door takes Wario to the hat switch he saved at. If he has not saved, it will return him to the beginning of the episode. If Wario wants to get rid of it, he must wait for it to vanish or draw poop to run into the door and destroy it.