Yoshi

Yoshis are NPCs that can be ridden by Mario and Luigi.  They come in 8 colors, each with a different ability. All yoshis can use their tongue to eat another NPCs (but not all of them are edible) and are immune to Chompers. they can also be jumped off (alt jump) to jump to a higher place or save the rider from falling down a hole. Unlike in the original Super Mario World, Yoshis can hold things on their mouth for an unlimited amount of time, as they don't attempt to eat. Yoshis will run around when hurt, but they are invincible, except for holes and lava.

Colors and abilities
Green Yoshis have nothing in special. They can shoot shells back at foes.

Blue Yoshis can fly for a limited amount of time when holding something in their mouths.

Yellow Yoshis will release dust when stomping the ground while with something in their mouths.

Red Yoshis will release 3 fireballs when spitting shells.

Black Yoshis will have the power of Blue, Red and Purple all at once.

Purple Yoshis will ground pund by pressing "down" in mid-air.

Pink Yoshis will spit out veggies every time he eats an enemy.

Teal Yoshis will spit out ice blocks every time he eats an enemy.

Shells and abilities
Green Shells will be spit out and will bounce off walls, killing any enemy in it's path (including the player)

Fire Shells will be spit out in 3 fireballs in 3 directions that fly off piercing anything.

Yellow Shells will create a dust-effect upon landing. When spit out they behave like Green Shells.

Blue Shells grant the ability of flying for a limited time. When spit out they behave like Green Shells.

Rainbow Shells grant all abilities at once, except the Green Shell.

Trivia

 * Toad has unused riding sprites.
 * The Yoshi's Tongue can't be found on the graphics folder. The tongue is hard coded and cannot be modified.