Spelltwine is a rare Sorcery card from Duel Decks: Jace vs. Vraska (DDM), collector number 34. Current market price: $0.29, TCGplayer market prices via Scryfall.
Exile target instant or sorcery card from your graveyard and target instant or sorcery card from an opponent's graveyard. Copy those cards. Cast the copies if able without paying their mana costs. Exile Spelltwine.