"Toon Zelda & Sheik" are names that are stored on the Super Smash Bros. Brawl game disc. Though no such characters appear in the final retail version of the game, hackers discovered a character file package in the game that was designated for the two, indicating that the pair was once planned to appear in the game.
Some speculate that "Toon Sheik" may refer to Tetra, as Sheik has never been depicted in a The Legend of Zelda: Wind Waker-influenced art style. However, noting that Sheik had never been depicted in a The Legend of Zelda: Twilight Princess-influenced art style either prior to Brawl (although Sakurai stated on DOJO!! that Sheik's Brawl design was based on unrevealed Sheik concept art made for Twilight Princess that was ultimately cut from the game), along with the choice of the name used, it may be more probable that the developers were planning on designing a new Sheik model, in the same manner as what was done with the standard version of the character in Brawl, or that such a model had been designed but ultimately unused in any of the The Legend of Zelda games. Because the programming is incomplete, the original intentions remain unknown.