Yoshi Bomb

From SmashWiki, the Super Smash Bros. wiki

Yoshi Bomb (aka "Hip Drop" or "Ground Pound") is Yoshi's Down B move. He smashes straight downward into the ground when used, and releases a star on either side, stunning enemies. If used on the ground, Yoshi will jump forward before dropping down. This move can be canceled by grabbing the ledge while dropping.

In Super Smash Bros. Brawl, the Yoshi Bomb has been weakened. However, it can hit enemies twice if used on the ground.

The move has become a somewhat standard move in Mario games, originating in Super Mario World 2: Yoshi's Island where Yoshi could use it to pound down stakes, crush crates, and slam through soft dirt. It is unknown why the move is called "Yoshi Bomb" in the Smash Bros. series despite never being known as such in any other game.

Yoshi's Special Moves
Standard Special Move:	Egg Lay
Side Special Move1:	Egg Roll
Up Special Move:	Egg Throw
Down Special Move:	Yoshi Bomb
Final Smash2:	Super Dragon
1: In Super Smash Bros. Melee and Super Smash Bros. Brawl only. 2: In Super Smash Bros. Brawl only.