Rainbow Mario
Rainbow Mario is a special form of Mario that appears in Super Mario Galaxy. Mario can reach this form by getting a Rainbow Star. As Rainbow Mario he is invincible, much like when he gets a Starman, but he is also faster and leaves a light trail behind. If Mario doesn't stop running while in this form, he'll get star bits (but obviously, if he doesn't run or runs in small bursts, he won't get any star bits at all).
Rainbow Mario's theme is re-orchestration of the same theme of Wing Mario from Super Mario 64. The music as well as Mario himself will increase in speed while in use, making Mario get harder and harder to control until it runs out.
Due to the traits of invulnerability, changing colors, increased speed, and leaving after-images, this form is similar to Hyper Sonic of the Sonic the Hedgehog series.
Differences between Star Mario and Rainbow Mario
Rainbow Mario last longer. Rainbow Mario has a small speed increase. Rainbow Mario can break through certain objects that Star Mario cant.
