Alquist Proft, Master Sleuth

The activated ability is the whole thesis: a repeatable X-draw stapled to a body, with the Clue economy setting the meter. Most X-draw payoffs in these colors are one-shot spells that empty your hand to refill it; this one converts a single standing Clue into a pile of cards and life at instant speed, and the size of that refill is capped only by how much mana you can pour into X. The self-investigate on entry hands you the first Clue to fuel an activation, but the design clearly wants a steady supply of them so the ability can fire turn after turn, which pins the card's power to how much incidental artifact-token generation the rest of the deck brings. Vigilance is the quiet load-bearing piece: a 3/3 that can attack and still hold up the activation at end of turn means the body and the engine never compete for the same tap. The tension the design resolves is that flashy draw-X effects usually ask you to go all-in on one turn and pray it resolves; here the burst is banked in a Clue you made at your leisure and a mana total you choose when the coast is clear, rather than gambled on the stack. It is a card advantage engine dressed as a beater, and the closer the deck sits to artifact tokens, the wider the gap between the printed rate and what the sleuth actually returns.