This marks the 6th show created by Genndy Tartakovsky for Cartoon Network Studios after Dexter's Laboratory, Samurai Jack, Primal, developed Star Wars Clone Wars, and co-created Sym Bionic Titan.
Quite a few homages to other shows. The bad robots look like they come from several studio ghibli creations, the robot that brings 'emma' back looks like tik-tok from the oz stories, the wizard who tells the heroes they'll return looks like Darkwolf from Ralph Bakshis Wizards.