Cosmic Luigi

Cosmic Luigi is a character who appears in Super Mario Galaxy. He replaces Cosmic Mario in Super Luigi Galaxy, he's very similar to Cosmic Mario the only difference is he takes advantage of shortcuts very often and uses a lot of Long Jumps so he is faster and much harder to beat than his counterpart.

In Super Mario Galaxy 2 despite not being in the game while playing as Luigi Cosmic Clones behave very similar being slightly faster.