Way Before Dragon Ball GT, 1 Mysterious Character Foretold the Debut of Super Saiyan 4

In Dragon Ball GT, Goku and Vegeta managed to attain a level of power that, until the release of Dragon Ball Super and Dragon Ball Daima, was the be-all end-all transformation in a series chock-full of them. Dubbed Super Saiyan 4, this form not only looked badass but gave Goku and Vegeta abilities that made all their previous transformations look tame in comparison, with Super Saiyan 4 originally foreshadowed by a character hailing not from Dragon Ball GT, but from Dragon Ball Z!