The Aether Flues (Planechase Anthology)

When you planeswalk to The Aether Flues or at the beginning of your upkeep, you may sacrifice a creature. If you do, reveal cards from the top of your library until you reveal a creature card, put that card onto the battlefield, then shuffle all other cards revealed this way into your library. Whenever you roll Chaos, you may put a creature card from your hand onto the battlefield.