UFO Robot Grendizer vs. Great Mazinger (UFOロボ グレンダイザー対グレートマジンガー UFO Robo Gurendaizā tai Gurēto Majingā) is a 1976 animated short film that crosses over Go Nagai’s super robots Grendizer and Great Mazinger. The movie features alternate versions of events from both series and as with the rest of the Vs. films is not canonical to either one.