A Warp Pipe is a common item in the Mario universe. Even though every pipe in the Mario universe in considered a Warp Pipe, only some are used to transport a creature from one point to another point. In many cases, Warp Pipes can be used to cross great distances (and even worlds), instantly. The size of Warp Pipes can vary, with some being too narrow for Mario to enter. They are traditionally green, but have appeared in many colors in lesser numbers over the years. Warp Pipes are also commonly used as homes for Piranha Plants and some Lakitu. The behavior of pipes can also vary, with some even expanding and contracting.
- An exit enabled pipe in a screen without a designated screen exit will send Mario to Level 0 or Level 100, depending on the level number. Levels 0-FF will send Mario to Level 0, while levels 100-1FF will go to Level 100.
- Pipes actually use four palettes: 4, 5, 6, and 7. They cycle through the palettes every four screens.
- Entering a pipe with a Silver P-switch will cause it to act like a Blue P-switch in the next room.
- If a warp pipe is placed next to a screen boundary, the screen exit from either boundary can be used by it, depending on how far on the right or left of the pipe Mario is. If you have to put a pipe there, be sure to put the same exit on both boundaries.
- Entering a pipe on the same frame Mario dies will result in the next room's music being replaced by the death music.
- Entering a pipe while Yoshi's tongue is extended will cause him to glitchily stick it out twice upon entering the next room.
- If Mario gets a powerup while entering a pipe (via Yoshi's tongue), the entrance will be cancelled. This is known as the "Layer Switch Glitch", because the game thinks you're still in the pipe. The Yoshi will be forever stuck in it's pipe-entering animation, Mario will lose interaction with most sprites, and he's pass behind Layer 2.
- If Mario is holding an item when he does the Layer Switch Glitch, that item will become stuck to his chest, and he won't be able to drop it.
- If you enter a pipe (or door) 256 times in a single level, the game will glitch and send you to some other level than the screen exit calls for. This can be fixed by hijacking $00D273 and changing it from INC $141A to LDA #$01 STA $141A.