The Soothsayer's Deck is an oracle deck of 36 cards constructed specifically to provide interesting twists on actions, for tabletop roleplaying. It can be used as the central device for resolving action, as an augment to add on top of another game (especially diceless games like Amber and the like), for GM prompts, or even as an in-game device, as you like.
For an example of the deck as a resolution... [click here for more]