Midair Shell Jump
Midair Shell Jumps, or Midairs for short, are one of the hardest tricks in the game. Even without using a wall, with precise enough inputs, you can throw a shell forward from behind you and get a bounce off of it in midair, allowing you to cross extra large gaps or gain extra height for cheese or secrets.
There are a couple different techniques for midairs, and both have their pros and cons. The flick method is ideal for speedruns, because you maintain your full momentum without momentarily losing P-speed. However, they are slightly luck-dependent, and they can only be done with P-speed. The tap method is ideal for consistency, and required for no-p-speed midairs, but they require a more precise frame-perfect throw, as well as more overall inputs.
In order to get a midair, you need to be moving as fast as you can, and you need to throw the shell forward but from as far behind Mario as possible. The hardest part of midairs is keeping enough speed so that the shell is still under you by the time you can land on it, 16-17 frames after throwing the shell.
Flick midairs abuse the turn-around animation while Mario is switching directions while holding an item. You can initiate a 360 turn-around by quickly flicking the d-pad from left to right, and then throw in the middle of that 360 turn-around animation to have the shell throw forward from behind Mario. The animation takes about a quarter of a second (16 frames) to play through, and you want to throw around the middle of that, anywhere from 8-12 frames after the flick, when the shell is behind Mario. If you throw fewer than 8 frames after flicking, the shell will throw left instead. Otherwise, if it threw right and you missed, either you threw too late so the shell wasn't far enough behind Mario, or you lost too much speed. Similar to a wall shell jump, if it kills you or goes over you, you threw too late, and if it goes under you, you threw too early.
- Get up to P-speed with a shell in hand, and jump, holding Y, right, and B.
- Quickly flick your d-pad left to initiate a turn-around animation, and flick back to holding right again as soon as you possibly can to get back to full P-speed. If you're too slow with these inputs, you might lose too much speed.
- Shortly after the flick (8-12 frames), let go of Y as briefly as possible to throw the shell before holding Y again. If you let go of Y too long, you will lose too much speed.
Note: The audio in this video can be used as a timing reference for the 8-12 frame delay between the flick and the throw.
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