Isperia the Inscrutable
The combat trigger is built on a guessing game, and that is what makes this Sphinx an oddity rather than an engine. Most card-advantage payoffs on a creature ask you to connect; this one asks you to connect and name correctly, reading the opponent's hand for a card you already suspect is there. When it hits, the reward is narrow on purpose: not any card, but a creature with flying, fetched straight to your hand and shuffled away. The shape rewards a deck that already knows what it wants to draw, a deck thick with evasive threats where the "choose a card name" gamble becomes near-automatic because you are searching for one of many redundant fliers and naming the one you most fear opposite you. The 3/6 body is the quiet design counterweight: a 5-mana legend that taxes a guess for its value has to survive long enough to swing, and toughness six holds the ground while the flying gets the trigger online. It is a tutor stapled to a wall stapled to a riddle, and the riddle is the part that has kept it a build-around curiosity rather than a staple. Sphinxes in this slice of blue-white tend to traffic in information and inevitability; this one literalizes the theme, turning the act of knowing your opponent's hand into the resource it spends.

