I've been playing Dark Souls and, I must say, this is a perfect Halloween game. Nearly every area is just a haunting ground (TM) of eerie looking creature that are out to do one thing: kill you.
Let's look at where I am now as an example. I'm in this area called the Painted World of Ariamis. To actually get there, you need this grotesque looking doll that needs to be found in a decrepit, rundown asylum. Then, you need to examine a painting that literally pulls you into the world. When you walk across the busted wooden bridge, you see bodies upon bodies impaled on spears. The enemies that are trying to end your life are ones you've encountered before, plus some new ones. The new ones so far have been:
Engorged Hollows: Enemies with giant boils taking over their upper half. Eww.
Crow Demons: These things are as tall as Slender Man and they just look...mean. They will latch onto you and peck your eyes out.
Phalanx: Ok, I've seen some gross things before but these are just vile. Hollow heads, slug bodies, and the ability to chuck massive spears? Yikes.
And I think I'm just getting started. This is a great game, and it's also a great game for Halloween. While clearly designed as an action/RPG with a heavy emphasis on dungeon crawling, Dark Souls' brutal difficulty and haunted atmosphere make this feel like a survival/horror game in many ways. I can't believe I waited so long to play this, especially since I enjoyed Demon's Souls so much.