If you loved Ultraman Saga, try Ultraman Zero: The Revenge of Belial
A bridge between a film you've already seen and one most people haven't. Here's what they share, and what the second one does that the first one doesn't.
What they share
Theyboth carry the playful mood tag, and they sit in Action / Adventure / Family / Science Fiction territory. If that's the register that drew you to Ultraman Saga, the second film will land in a comparable space — through a different lens.
playful
What Ultraman Zero: The Revenge of Belial is
Here's a film that wants to recapture the glory days of Japanese superhero movies. A young Ultraman must face Kaiser Belial, who has returned seeking revenge. It's a fairly standard good-versus-evil story, but with more spandex.

