Yoshi Kart (form)
Yoshi Kart (ヨッシーカート, Yosshī Kāto) is an original transformation that appears on two occasions in Super Mario-kun.
In chapter 13 of volume 6, while on a race to find the Pretty Kinoko, Bowser destroys Mario's kart with a Big Steely to slow him, Luigi, and Yoshi down. Mario quickly grabs the broken kart's parts and shoves them into Yoshi's mouth alongside a Super Mushroom, turning him into Yoshi Kart. The Mario Bros. ride him and chase Bowser. Later, after planning on how to defeat the Pretty Kinoko, Mario lures the giant mushroom into chasing him while driving Yoshi Kart, then, as soon as they reach the Bob-omb minefield, Mario applies some Wings on Yoshi, making him fly to safety while the Pretty Kinoko runs straight into the minefield.
In chapter 12 of volume 7, an obese Mario and Yoshi attempt to chase Lakitu that just stole Yoshi's oseibo. Mario goes to his kart, breaking it under his weight, so he shoves the kart parts into Yoshi's mouth. While chasing Lakitu, Mario makes Yoshi spit a Green Shell at him, making him drop the oseibo that is quickly stolen by a Para-Goomba. While chasing him, several members of the Koopa Troop run at them, but they all end up in Yoshi's mouth. Having realized he ate a red Koopa Troopa, Yoshi Kart turns himself around and spits fire, gaining speed. After they crash straight into a pipe, Mario dismounts him and defeat the enemies by himself. During the fight, one of Birdo's eggs hits the back of Yoshi's head, making him spit out the kart parts, turning him back to normal.