I would give this a gore rating of 2 out of 5 on the gore scale. There some Lovecraftian variety of ick--there is some tentacular horror--and there's a funny talking headless corpse which gets a minute or so of screen time, and there's also a spooky bloody girl who pops up a few times and one zombie. There's also some crime-related violence. To tell the truth, I think the evil book which oozes goo is the grossest thing in the movie.