Mechan Assembler

The rate-limiter is the whole design conversation here. A trigger that spawns a 2/2 whenever another artifact you control enters is not new; payoff engines rewarding artifact density have existed for years, and left uncapped they scale toward the absurd the moment you chain cheap artifacts in a single turn. The "only once each turn" clause is what keeps this from becoming a token-burst combo piece: it converts an explosive engine into a grind-forward value creature. But the wording is doing more than it looks. "Once each turn" is not "once on your turn": the trigger is live during every player's turn, so a deck built to blink or flash artifacts in on opponents' end steps can bank a second and third token across a full turn cycle. That widens the plan from a passive drip into something you actively schedule around instant-speed artifact drops. Even so, the clause caps the burst potential the effect would otherwise carry, asking you to reliably deploy one artifact per relevant window rather than storm off with zero-cost fodder. The 4/4 body matters to that plan: a five-mana creature that also builds an army needs to survive the turn it lands rather than trade down immediately. The Robot Artificer typing points at where the engine wants to live, in a shell already committed to playing artifacts every turn, where the token is rent collected on a plan the deck was running anyway. A self-limiting take on the artifact-token payoff, with the timing window quietly wider than a first read suggests.