One Deck Dungeons, Abyssal Depths, is a new mini expansion for One Deck Dungeon. It adds six new Fiend cards & three new Heroes that can be used with One Deck Dungeon, or Forest of Shadows Expansion. The new rules for Fiends give players a fresh new way to explore the dungeons, and is full of tactical, strategic choices to be made about how they`ll tackle the new threats!