Hypnotic Siren

Bestow was built on a tension: come down cheap early or arrive late as an aura, and one card has to justify both modes. Most of the cycle resolved this by being a serviceable body up front and a modest pump aura later. This one inverts the priority. Cast for a single blue, it is a 1/1 flier and little else, a play you make to fill a slot rather than to win a fight. The reason to run it lives entirely in the back half. Pay the steep bestow cost and it stops being a buff: instead of merely handing the enchanted creature +1/+1 and flying, it hands you control of that creature for as long as the Siren stays attached. That theft clause is what sets this one apart, since its cycle mates trafficked exclusively in stat boosts. Seven mana buys a steal that holds through most board states, and bestow grants the maneuver a graceful exit: if removal answers the aura, the Siren dies like any Aura, but if the stolen creature itself leaves, the Siren simply unattaches and stays on your side as a 1/1 flier rather than following it to the grave. The discipline is in the gap between the two modes: a throwaway early drop and a backbreaking late one, sharing a card slot, with the player choosing which game they are in.