We've got everything from trolls to dragons to fairies to aliens living on the bottom of the sea, so the only thing I can think of is a little child that somehow aqcuired Pretender God powers.
It'd be a different Pretender, and it'd play on the psychological effect of encountering something regarded as harmless (a kid), but which is in reality a powerful threat. A bit akin to those scattered stories you hear in the news about a family's friendly lap-dog suddenly going berserk and killing everyone in the house. Hey, maybe that's an idea
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