So last Friday, Cryptic offered a testing/preview of their first free add-on content, "Blood Moon". Due for live release on October 27th, it features instances and PvP with an Undead/Werewolf theme.
I only got a chance to try the PvP. Normally, I frikken HATE PvP, but this managed to be entertaining, fun, and griefer-free, for the most part. There were a couple incidents of respawn camping, but all in all not bad since the respawn points change.
You start out in a cabin in the woods, if you start as a hero, or in a cave if you're the unlucky soul who starts as an undead. You try to survive as long as possible. If you fall against the undead, you respawn as undead. The game continues as long as there is one living hero left.
I'm actually looking forward to the chaos on the 27th. :D