Ultraman: Great Monster Decisive Battle.

A 1979 Japanese tokusatsu kaiju film produced by Tsuburaya Productions, consisting of re-edited material from the original television series Ultraman. Ultraman: The Great Decisive Battle was the 1st movie of the third Showa phase (Jissouji's Ultraman being first and Ultra Brothers vs. The Monster Army being second) and because of this Tsuburaya decided to make this a reunion of the last 12 Ultras (aside from Ultraman 80 which hadn't come out yet). Tsuburaya decided to give this a different tone than Jissouji's Ultraman, having more new scenes and appealing to the all-Ultra fan.