Samus Aran
Samus Aran is an intergalactic bounty hunter who occasionally visits the Mushroom World.
In Super Mario RPG, Samus traveled to the Mushroom Kingdom to stay at the guest room of the royal castle. Apparently, Samus needed a place to rest before battling the evil Mother Brain.
Interestingly enough, the maniacal Booster owns a Samus Aran doll.
Samus was also going to appear in Mario & Luigi: Superstar Saga where she would try a sample of coffee at the Starbeans Cafe, but she was replaced at the last minute with Professor E. Gadd.[1]
Samus also appears in Super Smash Bros. and Super Smash Bros. Melee, as a playable character. She is due to appear in the forthcoming Super Smash Bros. Brawl, as both her normal suited self, and also as Zero Suit Samus.
