In universe, I mean. Where do they all come from? Are they all related?OK, I had to look that phrase up.
The Eldritch Abomination is a type of creature defined by its disregard for the natural laws of the universe as we understand them. They are grotesque mockeries of reality beyond comprehension whose disturbing otherness cannot be encompassed in any mortal tongue.
Eldritch Abomination - TV Tropes
So now that I am clear, a short answer is, he is a major fan of H.P. Lovecraft and he likes to scare people.
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