Octoboos are the ghosts of Octoombas appearing in Super Mario Galaxy 2. 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 do not spit rocks. Brand new Super Mario Galaxy 2 is a platforming video game developed by Nintendo for the Wii. It was first announced at E3 2009 and is the sequel to Super Mario Galaxy.