Nightmare Void is a uncommon Sorcery card from Ravnica: City of Guilds (RAV), collector number 100. Current market price: $0.14 (foil $0.35), TCGplayer market prices via Scryfall.
Target player reveals their hand. You choose a card from it. That player discards that card. Dredge 2 (If you would draw a card, you may mill two cards instead. If you do, return this card from your graveyard to your hand.)