If you loved Overlord: The Undead King, try Overlord: The Dark Hero
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
Both films are directed by Naoyuki Ito, and they both carry the 3am cult, epic, foreign gem, playful mood tags, and they sit in Action / Adventure / Animation / Fantasy territory. If that's the register that drew you to Overlord: The Undead King, the second film will land in a comparable space — through a different lens.
3am cultepicforeign gemplayful
What Overlord: The Dark Hero is
You rule a virtual realm as a powerful overlord but then dark secrets surface. The series' creator balances action and fantasy.

