Geno (ジーノ, Geno) is a character from the Mario universe. Unlike most characters from this universe, he was not originally created by Nintendo but instead by Squaresoft (now Square Enix) for the 1996 title Super Mario RPG: Legend of the Seven Stars.
Geno is one of the two original party member characters from Super Mario RPG: Legend of the Seven Stars, the first Mario RPG title. Geno is a warrior from Star Road who allies himself with Mario, Princess Peach, Bowser, and Mallow on their quest to defeat Smithy. Geno's true form is enigmatic, represented in-game by a small star; as an agent of the Star Road, he is implied to be an angel-like being who claims to serve "a higher authority." His true name is given as "♥♪!?" (which he describes as "hard to pronounce"), so he suggests using "Geno", the name of the doll that he has chosen to possess.
Due to Super Mario RPG having been developed by Squaresoft, its original characters are owned by them rather than Nintendo despite the fact these characters were created for the Mario series and not for any other franchise. As a result, they have made very few appearances in other media; Geno's only game appearance after his debut was in a brief cameo role in Mario & Luigi: Superstar Saga in the minigame Star 'Stache Smash (with a quick mention of Square Enix as the copyright holder in the game’s credits). Notably, this cameo was removed in the game's remake, presumably for licensing reasons.
While Geno does not appear in Brawl, Sakurai has considered his inclusion as a fighter since he knew about the character’s popularity and felt he could easily fit in the game. However, this consideration fell through, presumably due to him being co-owned by Square Enix, along with Nintendo.
Geno appears as the basis of a downloadable content costume for Mii Gunners. Nintendo also released a QR code for those who wish to have the exact Mii used in the costume's advertising. The Geno costume was released simultaneously with Cloud, Midgar, and the Chocobo hat, collectively introducing Square Enix content to Smash.
Geno appears as a profile icon in the game's online mode, and also appears as a spirit in the game's Adventure Mode, World of Light. His Spirit Battle has the player fighting Sheik (representing Geno himself) along with Mario, Peach, Bowser, and a gray Kirby (representing Mallow), who comprise the primary cast from Super Mario RPG. He is a Legend-class spirit and can be found in the Light Realm’s outer-space section in the map’s northern portion, roughly northwest of Peppy’s training facility.