Metalworker

The mana math runs backward from every other accelerant ever printed. Most ramp scales off what sits in play: lands, deployed creatures, permanents already committed. This scales off what you refuse to play, paying out two colorless for every artifact still sitting in your grip. A pile of cheap, otherwise-dead artifacts that would normally read as a clunky hand instead becomes a battery: tap this creature, reveal the stack, and each card revealed is worth two colorless. The artifacts never leave your hand, which is the quiet engine of the whole thing. The reveal costs nothing, so refilling the hand and re-tapping repeats the trick without ever spending the cards you are counting. That inversion is the entire point: it punishes a tidy curve and rewards a glut, asking you to hoard rather than develop, then dump the stored mana into something a fair deck cannot survive. The friction lives in the body. A 1/2 that produces no mana on arrival and folds to any removal aimed at it, so the whole plan rides on it living through a rotation. It became the heart of the combo decks that defined high-power artifact strategies for years afterward, the card that turned "draw a hand of artifacts, win this turn" from a fantasy into a reliable line. Few creatures so unimposing have drawn this much banned-and-restricted scrutiny across the formats where it is legal.