If you loved Attack on Titan II: End of the World, try Giant God Warrior Appears in Tokyo
A bridge between a film you've already seen and one most people haven't. Giant God Warrior Appears in Tokyo has roughly 8.0× fewer votes than Attack on Titan II: End of the World — it's a deeper cut, not a mainstream recommendation. Here's what they share, and what the second one does that the first one doesn't.

Attack on Titan II: End of the World

Giant God Warrior Appears in Tokyo
What they share
Both films are directed by Shinji Higuchi, and they both carry the dread mood tag, and they sit in Action / Horror / Science Fiction territory. If that's the register that drew you to Attack on Titan II: End of the World, the second film will land in a comparable space — through a different lens.
What Giant God Warrior Appears in Tokyo is
Shinjuku. Midday. A single shattered pane of glass. Colossal armored beings descend, blotting out the sun. Incandescent destruction follows. Hide your children. A brief, brutal kaiju tone poem in the mode of 1960s Toho.