Hunting Grounds is a mythic Enchantment card from Dominaria Remastered (DMR), collector number 359. Current market price: $1.15 (foil $1.52), TCGplayer market prices via Scryfall.
Threshold — As long as there are seven or more cards in your graveyard, this enchantment has "Whenever an opponent casts a spell, you may put a creature card from your hand onto the battlefield."