Leyline of the Void is a rare Enchantment card from Duskmourn: House of Horror (DSK), collector number 376. Current market price: $0.51 (foil $1.45), TCGplayer market prices via Scryfall.
If this card is in your opening hand, you may begin the game with it on the battlefield. If a card would be put into an opponent's graveyard from anywhere, exile it instead.