Jan Jansen, Chaos Crafter

Two sacrifice outlets pointed in opposite directions, welded onto a body given haste for one reason only: so it can start tapping the turn it lands rather than sitting idle a full rotation. Feed it an artifact creature and it pays back two Treasure; feed it a noncreature artifact and it hands you two Construct tokens instead. Each line is a one-for-two on game objects, so activating either nets an extra permanent, and the wrinkle is that the two lines feed each other: the Constructs you make are artifact creatures, so they fuel the first ability for Treasure, and the Treasure you make are noncreature artifacts, so they fuel the second ability for more Constructs. Both abilities share the tap symbol, though, so you convert one direction per turn absent an untapper; there is no free loop, just a steady drip of new artifacts entering and old ones dying. The Treasure and the Constructs are not the payoff so much as the exhaust: what the engine actually produces is a stream of artifacts entering, leaving, and being sacrificed, which is the resource everything worth building around this gnome cares about. The color identity does the framing, gesturing at the trinket-swapping, deal-making chaos the name promises, but under the hood this is a throughput engine gated by the tap and the untap step. Everything that turns the churn into a win lives on other cards; the gnome just keeps the parts moving through the door.