Tell me about laid-back multiplayer games

Hey guys
I'm looking for a multiplayer game I can play.
It should ideally be one where I get auto-matched up with other players (since I don't have any gamer friends :| ) And it shouldn't be any mmorpg's, since I alrdy play WoW, and that's far enough enough that. Should at best be a laid back game where it's just about having fun, exploring, advancing and so.
Any ideas? (Alrdy playing SC2, LoL, WoW, TF2 and WC3)

Dark Souls is pretty laid back and easy

Just stand around the Undead Church in the first area you go to as a human and you'll get matched up to fight people pretty often. Really fun stuff.