Rock Mario

Rock Mario is a new form first seen in Super Mario Galaxy 2, first appearing in the Boulder Bowl Galaxy. Mario can turn into this form when he touches a Rock Mushroom. By shaking the Wii Remote, Mario will transform into a giant boulder. In this form, Mario can roll around and jump, damaging enemies and big red crystals with items inside them. If Mario touches certain enemies or a wall, he will revert to his rock form, but can be turned back into a giant boulder if the player shakes the Wii Remote.

The form later makes a small appearance in the Freezy Flake Galaxy where it was used to collect Launch Star pieces. The Melty Monster Galaxy, however, made extensive use of the power up in two of its missions.