It amazes me what Monolith was capable of pulling with the Build Engine. The AI is great, Stephan Weyte gives an outstanding performance as Caleb and of course the Cultists are amazing. They also can be a pain in the ass on higher difficulties, especially the ones with Tommy Guns. I think most, if not all, of my deaths were due to being overwhelmed by them. Hands down the best FPS experience I had, a must play in my humble opinion.