Listen, it's not the worst horror movie that's ever been made, but neither is it all that great. To be honest, it's just like 90% of the horror movies out there - it's a bit meh.
The lead actor does a decent job, the others not so much. It's not a very scary film by any means, it's Eli Roth so of course it's gory, but scary? No. There is little to no tension throughout, and you don't actually see much of the killing (just children's body parts).
The idea was good, and the effects were also well done. Nevertheless, that doesn't save this from being just another average film within what seems to be an ocean of bang average horror films.
6/10.