A-Leyline of Resonance is a rare Enchantment card from Duskmourn: House of Horror (DSK), collector number A-143.
If this card is in your opening hand, you may begin the game with it on the battlefield. Whenever you cast an instant or sorcery spell that targets only a single creature you control, you may pay {1}. If you do, copy that spell. You may choose new targets for the copy.