Time to Reflect

White does not get unconditional one-mana exile, so this routes around the rate by demanding a board state first: a creature qualifies only if it blocked or was blocked by a Zombie this turn, which means the spell is inert in a vacuum and lethal once the tribe is committed. That gating is the price. It turns combat into the arming mechanism, upgrading an ordinary block into permanent removal that sidesteps regeneration, indestructibility, and graveyard recursion. The condition is a targeting check, not a triggered ability, and that distinction is the whole window: because the card only asks whether a Zombie was involved in a block this turn, it stays live at instant speed through the rest of the combat step. You can let the block resolve, watch your Zombie come up short against something larger, and exile that creature before it swings back. The Zombie does not need to win the fight or even survive it; it only needs to have been part of the matchup, and it does not need to be one you control (any Zombie's block, on either side, satisfies the condition). That is the quiet efficiency: a losing block becomes setup for a clean exile, and a one-mana instant erases a blocker the board could not otherwise handle. Outside a deck built to feed it, the condition reads as dead text; inside one, it is white exile that costs a single combat to switch on.