Metro: Last Light.
I don't really get scared in games with first person shooter elements, so the fact that I spent nearly 2 hours stuck on one point in that game because I refused to enter a point I knew involved giant radioactive spider monsters of nightmares is pretty damn impressive for me. Plus the karma system in the game actually made me feel bad for some of the choices I could make. I'm normally not that involved with the whole good/evil moments, but I feel that the absolute terror that I felt in earlier parts of the game made me really connect with the characters and the interactions I had with them. By the end of it, I was actually feeling really bad for the entire circumstance of quite a few of the characters. Particularly the Russian. God damn I felt bad for the Russian.