Pipes are a game element that can be used as platforms. They are 2 blocks thick and can be rotated and changed in size.
If you drag Mario into the pipe, it will lead you to the other Sub-area and you can place an exit pipe; Mario can then go in to one pipe and come out the other. Only ten sets of these pipes can be made.
Items can be placed in Pipes. When an item is placed in a pipe, the item will be spawned out of the pipe when Mario comes near the pipe. Only one copy of the item can exist at a time; if the item is collected or destroyed, another will be produced.
Enemies can also be placed in pipes. Piranha Plants and Munchers will pop out of the pipe to attack (unless Mario is on or directly next to the pope), then back in. If the plant is defeated, it will not come back. For other enemies, copies will continually emerge from the pipe.