Shell Jumps

Shell jumping is a trick that involves bouncing off of a thrown shell in mid-air, allowing Mario to cross much longer gaps or reach much higher heights than normal. Shell jumping is most easily done against a wall, as it's easy to land on the shell during its rebound, but for speedrunning it's more commonly done in midair to cross gaps such as in Yoshi's Island 4.

Wall Shell Jump

Wall shell jumps are the simplist form of shelljump, and involve throwing the shell at a block so that it rebounds back at Mario. The most difficult part of the trick is learning the timing; since the shell falls at about the same rate as Mario, it should be thrown near, but not at, the height of his jump.

Wall shell jumps are required for secret exits to reach both Star World 4 and Star World 5's secret exits without a cape or Yoshi, and can also be used to reach Vanilla Dome 1's secret.

Video: VD1 Shell Jump Source: Lambby

Video: SW5 Shell Jump Source: Lambby

Video: SW4 Shell Jump Source: Lambby

Midair Shell Jump

Video: Midair Shell Jump Tutorial Source: rezephos

Midair shell jumps allow Mario to scale large gaps or reach higher platforms when a wall isn't present. However, because Mario doesn't interact with a thrown shell for a short period of time, it can be difficult to keep up with the shell as it moves. The basic process is like this:

• Start Mario's jump. Hold A/B the full time.
• Near the peak of Mario's jump (but before reaching it), tap the opposite direction Mario is moving, to initiate a turn.
• Immediately after tapping, switch back to the forward direction again. This is to regain the lost speed from turning before Mario fully faces left.
• Shortly after, once Mario has turned all the way left, release X/Y to throw the shell and hold it again afterwards.

If done correctly, Mario should be able to catch up to the shell and subsequently bounce off without being hurt. Though this is slightly easier and more useful at full sprinting speed, it's still possible without a full P-meter, as long as you're accurate in the timing of your inputs.

A midair shelljump is required to reach the secret exit in Donut Plains 1 without a cape or Yoshi. Additionally, it's often used in Yoshi's Island 4 to clear the gap after the star without landing in the water.

Video: DP1 Shell Jump Source: Lambby

Video: YI4 Shell Jump Source: Lambby

Double Midair Shell Jump

Sometimes, one jump just isn't enough, and so, like any good trick, it can be chained. However, because pulling multiple jumps off in tandem is extremely difficult to do in real-time, usually the standard method isn't used for the first jump. Instead, a more simplified version is used for the first jump. Instead of kicking the shell at the height of a jump, it's instead thrown high into the air, then bumped into as Mario passes it while carrying the second shell. Mario is almost guaranteed to bounce off the shell from this, though at the cost of the height and some of the distance normally gained. Star World 3's gap is just barely long enough to be cleared even with this method, making it arguably the most difficult trick used in any route.

As it happens, chaining midair shell jumps is actually required to reach Chocolate Island 3's secret exit without cape or Yoshi.

Video: CI3 Double Shell Jump Source: Lambby

Beetle Jump

Buzzy Beetles are slightly different than normal shells in that when stunned, after some time has passed, the sprite will turn back into a normal enemy. This property allows for yet another type of shelljump, which involves carrying a Buzzy Beetle's shell until right before it reemerges. At that point, you can throw the shell into the air, let the Beetle reemerge in midair, then bounce off it as it falls.

As an alternative, you can actually bounce off a Buzzy Beetle without ever letting go of it at all. In order to do so, simply throw the shell upwards after stunning, then catch it as it's falling downwards. Then, when the Beetle is about to unstun, time your jump such that it unstuns while Mario is somewhere around the top of his jump. The Beetle will unstun, then instantly be bounced off of, without you having to do anything.

This is due to a quirk with how SMW handles carried sprites. When you grab a sprite, its horizontal and vertical speeds aren't actually cleared; instead, that happens when Mario actually throws the sprite. However, if Mario releases the sprite through other means - such as the Beetle returning to its normal state - that speed never gets cleared at all, so the sprite starts moving as fast as it did when Mario first caught it. So, by catching the shell as it's falling, you leave it with a high downwards speed. Then, when the beetle unstuns, it regains that speed... which causes it to fly right underneath Mario. It's very easy to perform, making it ideal as a safety strategy.

Beetle jumping can be used to reach Vanilla Dome 1's secret exit without a cape or Yoshi.

Video: VD1 Buzzy Jump Source: Lambby