Fat Guy

Fat Guys (also known as Big Guys ) are corpulent Shy Guys that debuted in Super Mario World 2: Yoshi's Island.

Super Mario World 2: Yoshi's Island / Yoshi's Island: Super Mario Advance 3
Fat Guys make their first appearances in Super Mario World 2: Yoshi's Island level Lakitu's Wall, and are uncommon enemies throughout the rest of the game. They come in two colors: red (which initially walk but will run if Yoshi stands on them) and green (which are always running). Fat Guys simply walk or run back and forth continuously, changing direction when they encounter a wall or a margin, unlike regular Shy-Guys which walk around and may stop and turn back on their own will. They are able to damage Yoshi if they bump into him, but Yoshi can attack them by eating and ingesting them. If spat back, they will resume their behavior.

Upon ingesting a Fat Guy, Yoshi receives a Giant Egg. Fat Guys can also be used as platforms to cross obstacles such as spikes, as they are not damaged by jumping and Yoshi can safely stand on them.

When Yoshi has three Giant Eggs at his disposal, all of the Fat Guys will disappear until Yoshi uses at least one of the Giant Eggs.

Yoshi Topsy-Turvy
While no regular Fat Guys appear in Yoshi Topsy-Turvy, a larger variant, known as King Debuhō, does.

Yoshi's Island DS
Fat Guys return in Yoshi's Island DS, where they behave similarly to their first appearance.

Yoshi's Crafted World
In Yoshi's Crafted World, red Fat Guys appear in Poochy's Sweet Run and Poochy's Magma Run and can be seen with different behaviors. Most simply walk back and forth on the ground and will start running after being jumped on, much like in their original appearance. They can be defeated by throwing an egg at them, charging into them with Poochy, eating and turning them into eggs, or Ground Pounding them. Ingesting a Fat Guy will fill Yoshi's egg stash instead of granting one Giant Egg like in past games.

Some Fat Guys stand in the background, pushing rectangular cutouts in Yoshi's way and rising them back up after a short time. Yoshi can stand on these objects while they are down as on a regular platform, and even ride them upward as the Fat Guys pull them back upright, much like Whomps can be used in New Super Mario Bros. and New Super Mario Bros. 2. In some cases, Fat Guys push these objects onto thin stilts and create a platform over a dangerous pit.

In Altitude Adjustment, pilot-themed, orange-robed Fat Guys make an appearance. Most drop down using parachutes to hinder Yoshi, but one pilots an airship at the end of the stage.

Paper Mario
In Paper Mario, an individual Fat Guy named Gourmet Guy makes an appearance as a gatekeeping NPC during the events of the fourth chapter.

Super Mario World 2: Yoshi's Island

 * Official Nintendo Player's Guide: Eat a Fat Guy to make a huge egg that turns every on-screen enemy into a star.