Toon Zelda and Toon Sheik are names that appear in Super Smash Bros. Brawl's programming code. Though no such characters appear in the final retail version of the game, hackers have 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 Wind Waker-influenced art style. However, since Sheik had never been depicted in a Twilight Princess-influenced art style either prior to Brawl, along with the choice of the name used, it would seem 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. Because the programming is incomplete, the original intentions remain unknown.