User blog comment:MarkvA/Sonic's Sidekicks: Who's The Best/@comment-5576601-20120413085045/@comment-3551372-20120413111945

@Mapsal Two characters in SegaSonic the Hedgehog that were to be Sonics sidekicks, but never had another playable appearance again. They've been seen around, and have been considered sidekicks for Sonic, but considering the idea was scrapped, we don't need them in the list.

They haven't been "Missing since 1993" for no reason.