Reconnaissance

The free activation cost is the whole trick: a zero-cost ability with no cap on uses turns combat into a question of how many attackers you can declare without consequence. Send everyone, watch the blocks happen, then pull your creatures out before damage. They keep the attack trigger and never take the hit. The parenthetical timing note is where the card stops being a defensive tool and becomes an engine: activate during the end-of-combat step and the creature untaps after it has already dealt its damage, so a board that should be tapped out and vulnerable on the crackback is instead standing up to block. That single line collapses the usual cost of attacking (your creatures tapped, you open) into nothing, and it does so at instant speed every combat for as long as the enchantment sits on the battlefield. Because the untap can wait until after damage, there is no tension between cashing in value and closing out the kill: an unblocked attacker connects for full, then stands back up to guard the return swing. The design reads like a minor combat trick and behaves like a permanent rewrite of the attack step. White's go-wide strategies have spent decades wanting exactly this: a way to send the whole team in without exposing it, to fire attack-based triggers risk-free, and to keep blockers home while still pressuring life totals. The only real cost is the one mana to put it down.