Thopter Assembly

A self-resetting token factory paying six mana for what looks like a 5/5 flier. The trick is in the upkeep clause: if this is the only Thopter you control, it bounces itself to hand and leaves five flying bodies behind in a single motion, so the same six mana keeps refilling the board across a long game. That oscillation between one beater and a five-body swarm is the whole strategic axis. The condition is also the leash. The moment you control any other Thopter, the trigger stops checking, the Assembly stays put, and the tokens persist; the engine only fires again once those tokens are gone. That gate is what makes sacrifice outlets and token-doublers worth building around, but it cuts both ways: every time you feed the five tokens to an outlet, you drive the board back to a state where the Assembly is once more your only Thopter, which bounces it to hand and asks you to spend the six mana again. You cannot hold the original on the battlefield while strip-mining its children; emptying the swarm is exactly what evicts the source. On its own it is a clunky midrange artifact. Built around, it is a renewable resource you ration deliberately, a design that reads less like a finisher than like a board reset you pay an upkeep and a recast to keep priming.