Portal 2 is a blast, has a shit load of humor and definitely a GREAT co-op game. If you plan to play co-op, do it with someone who hasn't beat it yet, at least for the most fun.

Great game, the best Horror game I've ever played, which honestly isn't very many. This game is extremely scary. I haven't beat it yet, but the style itself is great. You can't fight back, your method of staying alive is hiding like a little bitch! Definitely recommend for anyone who likes scary horror games. The biggest downsides to this game in my opinions are: You can't fight back, this definitely has its cons. Then of course how scary it is. It's extremely hard to sit for a long period of time, because you can get into this game so much. You MUST play this game alone, in the dark and with headphones for best effect. Check it out!