Thirsting Axe

A +4/+0 swing for three mana up front and two to equip is a fire-sale rate, and the design pays for it not with a static penalty but with a standing demand: every turn, the equipped creature has to draw blood from another creature, or you sacrifice that creature at your end step. The antecedent is the whole story. "Sacrifice it" points at the equipped creature, not the Axe, so the failure state is losing your beater and keeping the Equipment (now a stat-stick with no body to suit up). The rent is paid in combat damage to a creature specifically: not to a planeswalker, not to the opponent's face. Suit up a finisher to race a walker, swing into an empty board, or smash a defenseless opponent, and the +4/+0 does its job, but the creature dies at your end step for having connected with the wrong thing. The rhythm runs closer to a wager than a weapon, and it punishes the obvious aggressive lines hardest: removal on the only available blocker before damage, a fog, or an opponent who simply declines to present a creature all trip the clause. That target restriction is where it bites. The tension the card resolves is how to hand out four power for almost nothing without breaking the format, and the answer is a leash that tightens exactly when the board is at its most one-sided in your favor.