Descendants' Fury is a rare Enchantment card from Lorwyn Eclipsed Commander (ECC), collector number 93. Current market price: $0.30, TCGplayer market prices via Scryfall.
Whenever one or more creatures you control deal combat damage to a player, you may sacrifice one of them. If you do, reveal cards from the top of your library until you reveal a creature card that shares a creature type with the sacrificed creature. Put that card onto the battlefield and the rest on the bottom of your library in a random order.