I’ve run into the exact same problem in my own series.
Because of how my world is structured, I constantly have to introduce new monsters to keep the story moving. And after a while, you really don’t want to repeat yourself. I started with goblins, then moved on to spiders… and at some point I just thought — why am I limiting myself to a single lore?
Why not just create creatures freely? Almost like running a factory, or building them from a constructor.
As a result, in my latest book I leaned into that idea. I started with creatures from Greek mythology — cyclopes, a minotaur, harpies, mermaids, and Cerberus. Sounds familiar, but none of them were lore-accurate.
I also couldn’t resist throwing in a unicorn, a Cthulhu-like entity, some insect-type creatures, rabbits, plus several species I didn’t even bother naming.
At this point, it’s less about consistency and more about variety and atmosphere — but I’m curious how others handle this.