A-Leyline of Resonance

The A- prefix marks this as an Arena rebalance, and the balancing lever is worth naming: the paper version of this Leyline copied any instant or sorcery targeting a single creature you control, while the digital rebalance taxes each copy a mana. That is not a rounding error. Free spell-doubling with no downstream cost turns every pump spell, every Giant Growth effect, every targeted protection into a two-for-one that snowballs, and against a red aura or trample body it ends games out of nowhere. Charging one mana per copy reintroduces resource friction: you still get the copy, but you pay for it, so the machine gun becomes a decision rather than a reflex. The Leyline framing does the other half of the work. The opening-hand-into-play clause means the enchantment can be online before the game's first spell, which is the whole reason a heavily conditional four-mana enchantment sees play at all: it is not a card you cast, it is a mulligan-adjacent statement of intent. Everything about the design points at a targeted-spell aggro shell where the copy trigger is the payoff and the Leyline start is the enabler. The digital-only tax is a quiet admission that the free version copied a little too eagerly for an environment where the same interactions repeat thousands of times a day.