If you loved Mononoke the Movie: The Phantom in the Rain, try Blue Exorcist: The Movie
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.
You already loved

Mononoke the Movie: The Phantom in the Rain
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Blue Exorcist: The Movie
What they share
Theyboth carry the dread mood tag, and they sit in Animation / Fantasy / Mystery territory. If that's the register that drew you to Mononoke the Movie: The Phantom in the Rain, the second film will land in a comparable space — through a different lens.
dread
What Blue Exorcist: The Movie is
Tokyo streets at dusk with screams and screeching tires. Rin faces the Phantom Train and a mysterious boy devil. A darker anime fantasy from the early 2010s.