The combat trigger is the whole pitch, and it fires the turn you cast it: drop this in your main phase one, move to combat, and the counter goes on before you've even swung. You draw a card and lose one life immediately, before the opponent untaps into their sorcery-speed removal. In a format where Stomped by the Foot and Grounded for Life are the answers, getting paid on entry rather than on the attack step is the difference between a five-drop that ate a removal spell for nothing and one that already replaced itself.
BG Food wants it most. The archetype converts incremental resources into a life buffer (Anchovy & Banana Pizza and the broader food subtheme stitched through green and black), and that cushion is what lets the triangular life loss on the second and third triggers resolve without killing you. WB Legendaries is the other home, but for a different reason: white lifelink at common and the deathtouch-heavy black creatures keep the board contested long enough for a second swing, and the legendary payoffs reward the slot independent of the engine. UR Sneak treats it as a non-card despite black splashing easily through Escape Tunnel; that deck wants to be tapped out on a Sneak threat turn five, not casting a five-drop that needs protection to compound.
P1P1 the pack opens with it, P1P2 behind only Shredder, Unrelenting and the mythic Turtle legends. Maindeck in any black deck that can cast it. The deckbuilding question is the second black source, not the first copy. The punishers are common and real: Grounded for Life kills it tapped the turn after it attacks, and Dimensional Exile strands every counter.

