Stallion of Ashmouth

Delirium's whole pitch was the carrot for filling your graveyard with variety, and this is the common-rarity version of that promise at its plainest: a 3/3 body whose only trick stays locked until the bin holds four card types. The trade is honest. Before delirium comes online, the pump ability is dead text, so you are paying four mana for a vanilla body that swings for three and nothing more; after, you have a repeatable mana sink that grows it +1/+1 per activation, no cap, as long as the graveyard stays diverse. That gating is the design discipline. The pump cannot fire on a thin graveyard, so the card rewards the same self-mill, fetch, and disposable-permanent texture the rest of the mechanic was built to encourage, and it offers nothing to a deck that named delirium without committing to the supporting cast. As a Nightmare Horse it sits in black's middle, the kind of creature meant to give an attrition deck something to pour late-game mana into once the cards in hand run dry. It is filler in the precise sense the word should carry: a common doing exactly one job, asking you to earn the only line of text that separates it from a plain 3/3, and growing slowly once you have.