Octoboo

Octoboos are an undead ghost variant of Octoombas appearing in Super Mario Galaxy 2. They appear in the Haunty Halls Galaxy, Boo Moon Galaxy, and Flash Black Galaxy as regular enemies. In the first mission "A Glimmer of Bulb Berry", they are the first enemies to be encountered, and they can be found in groups while encircling a select area, behaving somewhat like Circling Boo Buddies or Peepas in later games.

In the second mission "Sneaking Down the Creepy Corridor", Boo Mario has to avoid these enemies to progress through the area. Octoboos resemble white, legless Octoombas with ghostly tails. They primarily move around by floating in a set area. Octoboos cannot be defeated; they become transparent, however when the player uses a Spin near them or from Yoshi's tongue. Octoboos also make small Octoomba sounds if Mario or Luigi is close to them. Unlike most members of the Octoomba family, they don't spit rocks.