Grim Leecher

Grim Leechers are enemies from Super Mario World 2: Yoshi's Island that exclusively appear in the level The Impossible? Maze. These enemies resemble purple ghosts with skulls on their faces. If Yoshi is a good distance from a Grim Leecher, they will wait until Yoshi comes, but then hover towards Yoshi if he comes too close. If they come in contact with Yoshi he will kick Baby Mario off his back and hop on Yoshi's back. This would cause the game controls to reverse and it also will cause Yoshi to change colors.

Trivia

 * Grim Leecher's name appears to be based off "Grim Reaper".