Grim Leecher

Grim Leechers are enemies from Super Mario World 2: Yoshi's Island, its remake, Yoshi's Island: Super Mario Advance 3, and Yoshi's New Island. These enemies resemble purple ghosts with skulls on their faces, and their name is a pun on "" and "".

Description
In Super Mario World 2: Yoshi's Island, Grim Leechers are found in extra and secret levels, appearing only in The Impossible? Maze in the original game as well as Mystery of the Castle? in the remake. They wait until Yoshi comes near and then hover towards them; if a Grim Leecher makes contact, they knock Baby Mario off Yoshi's back and hop on. This causes the game controls to reverse, signified by Yoshi turning a flashing pink color. Yoshi must Ground Pound to knock a Grim Leecher loose, and can eat them to produce an egg.

In Yoshi's New Island, Grim Leechers appear in the fourth level of World 2, Beware the Boo Brigade. They can no longer be eaten, and the Grim Leecher-controlled Yoshi is now colored purple.

A Grim Leecher makes an appearance in Super Smash Bros. Ultimate as a spirit.

Super Mario World 2: Yoshi's Island

 * Official Nintendo Player's Guide: This usuper kicks Mario off, hops on Yoshi's back and reverses your controls.

Yoshi's Island: Super Mario Advance 3

 * Shogakukan guide: ふれるとヨッシー背中にとりつき、ヨッシーの操作を左右逆にしてしまう. 赤ちゃんを取りもどせば、すぐに回復する. (When touched, it attaches itself to Yoshi's back and reverses Yoshi's movements from left to right. If the baby is retrieved, Yoshi will recover quickly.)