Hyperspeed Walking

Hyperspeed Walking (often abbreviated HSWing) is a glitch that allows Mario to build up speed while walking in steep slopes submerged in water. It is useful in many challenges including the A Button Challenge.

Execution

Steep slopes that normally could not be stood on can be stood on when they are submerged in water. If Mario walks uphill or perpendicular to uphill while standing on such a submerged steep slope, then his speed will decrease. There is no lower bound, so Mario can build up unlimited negative speed in this fashion as long as he can remain on the submerged slope.

Walls can keep Mario in place for small amounts of speed, but Mario will eventually break through them. Ceilings, which usually extend farther than floors and keep Mario in place rather than pushing him, are often more useful. Even better is Out of Bounds, which keeps Mario in place like ceilings do but extends forever, allowing Mario to build up far more speed.