What Dragon Ball, ONE PIECE and Toriko have in common? The three have long been - or have been - flagship anime, all produced by Toei Animation. The three very famous spiritual traits of Weekly Shonen Jump actually all ended up under the broad umbrella of the Edochian Company. They have long remained separate and defined universes.
This lasted until 2013 Toei Animation decided to create one special episode that makes up Dragon Ball, ONE PIECE and Toriko. At the time, ONE PIECE and Toriko were on the air and we were celebrating the start of the third year of production for the latter anime. There were no plans, at least not officially, for Dragon Ball Super, but Goku was still an all-too-beloved protagonist.
So the special episode was born "Dream 9 Toriko & One Piece & Dragon Ball Z Super Collaboration Special !!" who saw the three protagonists of Toei Animation collide. But it wasn't just the three stars who fought, as Mister Satan, Sanji, Chopper, Sunny, Zebra and many other characters from all three universes also appeared in the episode.
Some of the inspiration came from the Dragon Ball and ONE PIECE crossover called Cross Epoch. Did you also know that there was a cameo with Freddie Mercury in Dragon Ball GT?