Zirilan of the Claw

The exile clause is the whole pitch: this fetches any Dragon straight onto the battlefield with haste, then revokes it before your next turn begins. That borrowing structure is precisely what keeps tutoring your entire library for a single decisive swing a fair rate rather than a broken one; you get the attack, not the threat. But the verb matters more than the timing. The trigger exiles the Dragon, it does not sacrifice it, and exile only resolves on an object that is still where the trigger expects it. Flicker the borrowed Dragon, blink it, reanimate it, or move it to any other zone before that delayed trigger checks, and there is nothing left to banish; the Dragon stays for good. That seam between "exile this object" and "this object is no longer the same object" is the engine builders have spent years prying open, pairing the activation with sacrifice outlets, recursion, or any effect that shuffles the creature out from under its own end-of-turn death sentence. Taken at face value, the activation summons a haste-enabled Dragon for exactly one turn of damage and then erases it. Taken as a combo piece, it is among the oldest "summon a creature you cannot keep, unless you cheat" templates in the game, and the cheating is most of the draw.