Chill Bully

The Chill Bully is a variant of the Big Bully that appears in the Snowman's Land course. They appear in all versions of SM64, including the DS remake, though a different appearance as seen here.

Behaviour
The Chill Bully acts the same as a Big Bully, and drops a star when knocked into icy water.

There isn't a difference in behaviour, and thus, The Chill Bully is more of a texture/model swap of The Big Bully, who appears in Lethal Lava Land. However, unlike the Big Bully, the Chill Bully has a single horn on its head, preventing Mario from jumping on its head to push it back.

Trivia

 * Appearances of both The Chill Bully and The Big Bully can differ between copies.