Tri-Sentinel, Act of Vengeance

Seven mana buys a threat sized for a crowd. The 7/7 body carries flying and trample for the offense; menace muddies the block math; and the entrance trigger reaches every opponent at once, hitting up to one creature they control for three damage each. Heads-up that is a single removal shot, but across a full pod it strips a rank of small blockers, mana dorks, and utility creatures the same turn it lands, thinning the wall before the body starts swinging.

Unearth is what turns the one-shot into a repeatable board-punisher. Paying seven again returns it from the graveyard with haste, and because that is a fresh enter-the-battlefield event, the multi-target damage fires a second time: the graveyard becomes a launch bay for another round of table-wide burn plus a hasty seven-power swing. The exile clause reads like a leash on that engine, but it is a soft one. An unearthed Tri-Sentinel is set to be exiled at the next end step or the moment it would leave the battlefield, yet a blink effect (Ephemerate and its cousins) exiles it and returns it as a brand-new object, shedding the unearth restriction entirely and re-triggering the entrance damage. What looks like a strict one-and-done is really a floor: the ceiling belongs to whoever can rescue it into exile before end of turn. Each firing still costs a deliberate commitment, but the graveyard-to-battlefield loop is not as closed as it first appears.