Resonance Technician

Copy engines usually price their duplication in something fixed: a single spell, a single trigger, a per-turn cap. This 4/4 flier instead prices it in artifacts, and the exchange rate is variable. Tap X untapped artifacts, copy an instant or sorcery of mana value X, choose new targets: the size of what you fork scales directly with the board you can afford to bankroll, and the mana-value clause is the leash that keeps it honest. You cannot tap two trinkets to duplicate a game-ender; the payoff grows only as fast as you can assemble both the artifacts and an expensive spell worth copying twice. What makes the design cohere is that the enters-the-battlefield mode seeds exactly the fuel the tap ability wants. Pitch a dead card, get two Clues, and those Clues are artifacts to feed the copy while also being cards to sacrifice for draws later. The full loop reads as a self-contained resource economy: discard to manufacture artifacts, tap those artifacts to copy a spell, then cash the Clues in for the cards that keep the engine fed. Izzet has a long history of spell-doublers that reward casting big instants and sorceries for free, but those almost always double one spell with no board requirement. This one charges for every copy in tapped permanents and asks you to build a battlefield worth tapping before the payoff arrives.