Murciélago

In his sealed guise Ulquiorra is slim yet firmly built, with a mournful cast to his features: tousled short black hair, chalk-white skin, a black upper lip, and slit-pupiled green eyes set beneath heavy brows, teal tear-lines running down from each. A shard of his old Hollow mask crowns the upper-left of his head as a broken horned helm, and his Hollow hole sits at the sternum. He wears the Espada's white coat with unusually long tails and a raised collar.

The Zanpakutō Murciélago itself is a plain green-hilted katana whose guard splits into two curved, eye-like arms. Speaking its release word turns his energy into falling green rain and remakes him into a bat. Great black wings sprout from his back, his hair lengthens and wildens, twin horns curl forward from the mask fragment atop his head, his facial marks blacken into broad triangles, and his robe tightens around a body built for flight.

As the Espada standing for the death-aspect of nihility, Ulquiorra is detached and hollow to the core, certain that nothing holds meaning unless his eyes reflect it and that whatever he cannot see does not exist. He scorns the human 'heart,' waving off emotion as illusion, and cannot grasp the resolve that keeps Ichigo Kurosaki fighting, insisting the heart yields only pain and death. Cold, patient, and rarely rattled, he dislikes hurried talk and holds an even voice through nearly any situation.

That icy certainty cracks only at the very end. Fading away after his final battle, he reaches toward Orihime Inoue and seems, in his last instant, to finally grasp the feelings he spent his existence denying, discovering a heart of his own just as he dissolves into ash.

Ulquiorra's spiritual power is so vast that releasing Murciélago inside Las Noches could level the fortress, which is why the act is banned there. He excels at swift, precise swordsmanship yet prefers brutal hand-to-hand fighting, punching holes through his prey; he ranks as a Sonído master, boasts near-total high-speed regeneration of everything but his organs and brain, and rounds out his arsenal with Cero, Bala, a hardened Hierro, and a Solita Vista eye that stores whatever it sees.

Released, he grows far stronger and quicker, flinging green Luz de la Luna javelins and firing the black, green-edged Cero Oscuras. Uniquely, he can descend to a second tier, Resurrección: Segunda Etapa, which he names 'True Despair' for the crushing pressure it radiates; even Aizen has never witnessed it. In that state he sheds his coat, gains black fur and a long prehensile tail he swings as the whip Latigo, and hurls the Lanza del Relámpago, a lightning-forged lance that detonates on impact with blasts taller than Las Noches, though he struggles to steer it and shuns close range.