In Shroom City, Trap Floor is the final minigame played. It is played at the Pipe House, when Bowser challenges the player to this game for the final Gaddget. Winning gives the player the minigame and the Bowser Print.
The goal of the game is to open the trap doors to drop all the Koopa Kids to the floor below and eventually into the pits below the door. The opens the blue traps and opens the red ones; the can be used to open every trap, but it can only be used once. If a Koopa Kids fall through a trapdoor without opening the one below, it falls and bounces onto the ground beside it, dazed. Green Koopa Kids also move faster than the other types. If one of the Koopa Kids reaches the player, they lose.