Rakdos the Defiler is a rare Legendary Creature — Demon card from RNA Guild Kit (GK2), collector number 71. Current market price: $1.32, TCGplayer market prices via Scryfall.
Flying, trample Whenever Rakdos attacks, sacrifice half the non-Demon permanents you control, rounded up. Whenever Rakdos deals combat damage to a player, that player sacrifices half the non-Demon permanents they control of their choice, rounded up.