Dread Summons is a rare Sorcery card from Commander 2015 (C15), collector number 20. Current market price: $0.42, TCGplayer market prices via Scryfall.
Each player mills X cards. For each creature card put into a graveyard this way, you create a tapped 2/2 black Zombie creature token. (To mill a card, a player puts the top card of their library into their graveyard.)