Giant Egg

A Giant Yoshi Egg is an object used by Yoshis in the Yoshi's Island series. It is much larger than a normal Yoshi Egg. The Giant Egg can only be made if a Yoshi swallows a Fat Guy. Making their first appearance in Super Mario World 2: Yoshi's Island, giant eggs proved to be quite helpful in fighting difficult-to-defeat enemies, such as the final boss. They can defeat all on-screen enemies merely from the shock-wave they give off when thrown. In the final battle of the game, giant eggs are carried by balloons on the stage; the Yoshi must grab these and aim them at Baby Bowser's face (as a giant). Giant Baby Bowser will be defeated once successfully hit with a few giant eggs.

Giant eggs also appeared later Yoshi's Island DS; they helped the Yoshis fight the Final Boss. In this game, Yoshi has to throw Giant Eggs at Bowser in order to flip him over on his back to make Bowser vulnerable to a Ground Pound. Bowser could also grab the Giant Eggs and throw them at Yoshi. Kamek turns Bowser giant-sized for the last phase of the battle, which is similar to Super Mario World 2: Yoshi's Island. This time, four Giant Eggs are brought on the stage by one balloon. Each of the four Yoshis get one – then as all of the Yoshis aim the eggs at Bowser and throw them at him, Bowser will be defeated after a few hits.

Trivia

 * All of the giant eggs are colored green, except for the ones in the final boss fight of Super Mario World 2: Yoshi's Island, which are colored red.
 * When Yoshi has three or more giant eggs at his disposal, all of the Fat Guys will disappear. However, they'll reappear again once Yoshi has only one or two giant eggs left.
 * What could be a Giant Yoshi Egg appeared in Mario Kart 64, in the track Yoshi Valley.