Luigi

Mario's younger twin brother. He's shy, quiet, and overshadowed by his sibling, but he's actually quite talented. His jumping ability surpasses Mario's, and his all-around skills let him overcome any problem. He's a bit cowardly and really afraid of ghosts. Even so, in Luigi's Mansion, he was charged with cleaning up a whole house full of spirits.

(Source: Super Smash Bros. Brawl trophy description)