Death Keep seemed to be a fairly popular quest and i always wanted to do an expansion for it as it was originally written as a quick encounter. It is designed to play solo or co-op with no overlord (although there is no reason why you cant play with an overlord). It works like my other quests on a room by room adventure like a dungeon crawl.

I now have a completed its 2nd encounter which works as a push your luck style add on. If you feel healthy or lucky then push on and see whats in the hidden tunnels under the keep. You can bail out when you want to (although not during an encounter), but getting to the end will reap more rewards.

Death Keep - optionally uses forgotten soul cards (encounter 1) and natures ire cards (encounter 2)

The 2 other quests available :

Spiders Lair - optionally uses natures ire cards

Fire Caverns - optionally uses dark elements cards