Keil Fluge appears in Worlds Unite?

According to the Keil Fluge page on Wikia, “Keil appears in the crossover Worlds Unite, where he and the Blue Dragon defeat Gigabolt Man-O-War and Burn Dinorex and help Rotor the Walrus and Bubble Man destroy the Unity Engine set in his world.”

Does anyone have any more information to add to this? Any neat references to the series that we should know about?