Boo

Boos are ghost-like enemies in Super Mario 64. They are white, spherical ghosts with small hands and tails that appear triangular, with blue eyes and a mouth. They fly towards the player when not looked at, and freeze in place and go transparent when looked at. They are defeated by being ground pounded while not being looked at. They have a boss variant known as the Big Boo. They appear mainly in Big Boo's Haunt.