Skew
Skew is a specific form of movement in which Mario's in-game position changes where it is being tracked relative to Mario's model, and as a result causes Mario's hit sensors (informally known as "hitboxes" or "hit boxes") to rotate around the new position.
Execution
There are only a few ways to induce skew, due to the nature of how it works. Mario's feet must be at the center of his model or higher to initiate skew, which can be performed with the following actions:
- Performing a backflip
- Performing a sideflip
- Performing a triple jump
- Performing a vault
- Rolling
- Jumping from the top of a pole[1]
While Mario is upside-down or sideways in one of these animations, simply cap throwing will cause Mario's in-game position to instantly change to where his feet are at that moment.
Performing skew in the rolling state is slightly more complicated, as it isn't possible to cap throw directly out of a roll without instead doing a roll cancel, which automatically uprights Mario. Instead, Mario must long jump and then immediately cap throw, in a manuever sometimes called a "failed roll cancel", alluding to how players sometimes execute those inputs accidentally when mistiming the roll cancel inputs.
Properties
One of the most notable properties of skew is its ability to cause Mario to go out of bounds. The most recognized form of skew clipping is moon clipping, but other variants include damage clipping, bonk clipping, and the double-sided wall clip. Because of its ability to change Mario's position, it allows the player to get much closer to a wall or ceiling than what's normally possible. Certain animations, like taking damage or collecting a moon, then instantly place Mario's hit boxes completely upright, thereby placing them partially out of bounds, removing the rotation process the game does, which would normally prevent the clip.
Another useful property of skew is the ability for Mario to gain a large amount of extra height due to its "upwarp" nature. By utilizing two-player mode and the properties of a triple throw, it is possible to initiate a dive much earlier than normal, causing Mario to gain much more height than normally possible. Two-player mode is required to make full use of this extra height, since it allows performing a midair cap bounce at the peak of the dive.