Silverstrike

White doesn't get unconditional kill spells, so it gets removal that asks the opponent to commit to combat first. The "target attacking creature" clause does the balancing work here: the card is dead against a defensive board and useless on an empty battlefield, so it pays for its broad reach (any creature, no toughness cap, no protection clause to route around) with a timing window the opponent controls. That tension is the genre's whole identity, and white has cycled through versions of it for years: Reprisal answered big attackers, Divine Verdict dropped the toughness restriction, and this one folds three life on top to swing a race in the same breath it removes a threat. The lifegain is not incidental. Against an aggressive opponent, you both kill an attacker and pad the life total before the damage step, which is why this kind of card functions as a wall against early pressure rather than a flexible answer. It does nothing proactive and asks you to hold up four mana on the opponent's turn, but in the matchups it was built for it can buy back a creature's worth of tempo and a chunk of the life total in one card.