The Seventh Doctor

Free-spell payoffs usually gate themselves on a fixed threshold: cast the top card if its mana value is low enough, hit a converted-mana ceiling, or pay a life tax. This one hands the lever to your opponent instead, wrapping the payout in a guessing game where the number to beat is your own artifact count. That turns the Clue this card investigates into a live variable: every token you bank raises the bar the defender has to reason about, and since you're the one holding the chosen card, you always know which side of the guess is true. The design leans on asymmetric information. You see the card and the count; the opponent sees only the count and has to model your bluff. Whiff the guess and you cast the card for free at combat, ahead of the curve; guess right and you fall back to the Clue, so the ability never blanks. The 3/6 body is the quiet enabler here, a defensive frame that survives combat and keeps attacking turn after turn to reset the mind game. It rewards a build stuffed with artifacts and top-heavy cards you'd love to steal a turn on, and it asks a question no static threshold ever could: not "is this card cheap enough," but "can my opponent read me." That psychological axis, rare on a permanent that generates its own advantage even when the read goes against you, is what separates it from the usual free-cast engines.