Knight of the Last Breath

A conveyor belt for flying Spirit tokens that pays out two ways: the death trigger cashes it in for three at once, and the sacrifice ability launders any other nontoken body into one at instant speed. That loop elevates it above a plain afterlife creature; the Spirits it produces cannot feed themselves back through the cost, since the activation strictly demands a nontoken creature on the altar. So the design points you toward a battlefield full of expendable nontoken bodies: it wants a board that is dying anyway, turning a stalled ground army or a creature that would have chump-blocked into a widening air force of evasive fliers. Seven mana is steep for a 4/4, and the whole card is built around that friction: you are not buying the body, you are buying a repeatable sacrifice outlet that guarantees value coming and going. Kill it and the controller banks three Spirits; leave it and they grind incremental fliers off every creature that would have traded anyway. As an aristocrats piece, it asks for a graveyard-agnostic sacrifice payoff to sit under, since the value comes from bodies leaving play rather than from anything happening in the yard afterward.