Dr. Freezegood

Dr. Freezegoods are snowmen wearing buckets that are found in Super Mario World 2: Yoshi's Island, Yoshi's Island: Super Mario Advance 3 and Yoshi's New Island.

They ride ski lifts in World 5 and stand completely still unless they drop off on a slope. Yoshi cannot eat them, but he can step on their heads to rack up a few coins and defeat them. They are harmless to touch, though they push a Yoshi around when touched. Freezegood appeared in Tetris Attack, allied with Bumpty.

In Yoshi's New Island, they are found in Ski Lift Leap, where, in the first area, they are skiing down slopes while in the second area, one is seen riding a ski lift. They crumble when they are touched, and they do not spawn coins.

Super Mario World 2: Yoshi's Island

 * Official Nintendo Player's Guide: An extreme skier par excellence, the doctor of dare doesn't like dinos horning in on his icy turf.