Here is a lora created from 1167 rendered images.
Some good prompt words are, creepy, haunted, mutant, blood.
some setting were abandoned locations, cemetary, forests, carnival, prison, desert, cities
This gives scary and spooky images rather than real bloody, unless prompted.
Use <lora:SDXL Horror Style:1> sdxl horror style
Renders sometimes come out a little dark with hard lights and may need to be guided with prompts that add realistic lighting.