Ulquiorra Cifer

is the 4th Espada in Sōsuke Aizen's army of Arrancar. He is sometimes considered to be Neliel's equal in terms of power.

Arrancar arc
Ulquiorra first appears alongside Yammy when they arrive in Karakura Town to gain information on Ichigo Kurosaki. Ulquiorra retreats with Yammy once he finishes examining Ichigo's abilities, also taking note of Orihime Inoue's fate-manipulation powers. A month later, Ulquiorra sends a second group of Arrancar (not counting Grimmjow's rogue actions) consisting of several Espada, meant to distract the Shinigami while he captures Orihime. By threatening her friends lives, he convinces her to come peacefully, allowing her to say goodbye to one person beforehand.

Hueco Mundo arc
Upon returning to Las Noches, Ulquiorra claims that he has trapped Orihime in a psychological prison from which her loyalty to Aizen is guaranteed, though this proves to be false when Orihime resolves to ruin Aizen's plans. Ulquiorra reappears to fight Ichigo, which ends in a sound victory for Ulquiorra. He leaves Ichigo alive but badly injured, suggesting to him that he should retreat if able. After discovering that Grimmjow has taken Orihime, Ulquiorra tracks them down and engages in a short battle with Grimmjow, ending with Grimmjow using a portable negación field to temporarily trap Ulquiorra. He then escapes and is left in charge of Las Noches and is currently awaiting the arrival of Ichigo Kurosaki. While waiting, he questions Orihime if she feels any fear in knowing that she will die alone. She boldly answers no, and states she has confidence in her friends and Ichigo, and that she is not fearful because her heart is with them. Ulquiorra, unable to understand how she can harbor such feelings, presses her further. He asks her what a heart is, and reaches out to touch the area above her heart, asking where he can find it. But just as he is about to further interrogate her, Ichigo breaks in and is ready to battle. Ulquiorra then unsheathes his sword to eradicate Ichigo in order to protect Las Noches.

Appearance
Ulquiorra is a male arrancar with a melancholic appearance, short, messy black hair, silver skin, and green eyes with slit pupils. Cyan lines descend from his eyes, making it appear as if he is crying. His facial expression very rarely changes, and he is near-constantly frowning. He also appears to be the youngest member of the Espada, next to Szayel, Grimmjow, and Neliel. He wears typical Arrancar clothes: a white jacket, black sash, and a white hakama. They are somewhat similar to what Ichigo's Inner Hollow wears. However, his jacket seems to have longer coat-tails than others. Like most other Arrancar, he possesses remnants of his former life as a Hollow in his appearance. His hollow hole has moved; it is at the base of his throat as opposed to his chest. The remainder of his hollow mask lies on top of his head, forming a broken helmet, much like that of the example silhouette of a Vasto Lorde. He is the fourth-ranked Espada, signified by the tattoo on the left side of his chest.

Personality
Ulquiorra is a very cold, aloof, brooding, and callous figure, hitting his comrade Yammy in the stomach with his arm on one occasion in an effort to get his attention. He's also rather dispassionate, rarely showing any sign of emotion, appears depressed, and is rather indifferent, willing to harm both his comrades and enemies should they ever disrupt his plans. He tends to call anyone he does not find interesting "trash" and therefore expendable. Despite this, he is not particularly violent, only actually fighting when provoked or ordered to by Aizen. As noted by Grimmjow Jeagerjaques, Ulquiorra has a habit of stabbing people in the same location as his hollow hole whenever he's particularly interested in a battle. Whether he is consciously aware of this habit or not is unknown. However, his speech to Orihime indicates that he is, as he speaks of never seeing the "human heart (emotions)" that living humans possess and understand, and reasons that if his eye cannot see them, then they are not real. It would appear that as a result of his isolated life as a Hollow, Ulquiorra does not understand feelings and emotions as well as empathetic characters like Orihime tend to. His overall behavior towards his allies and enemies, as well as his apparently self-inflicted habit of stabbing people in the chest, may symbolize that fact. It should also be noted that Ulquiorra's hollow hole seems to have moved since his first appearance, as it is now located somewhere near his sternum.

Ulquiorra is also perceptive, cunning, and analytical; during his and Yammy's first visit to the human world, he makes several remarks on the humans who confront them. He theorizes that Orihime Inoue's healing power is a temporal-spatial ability, which Aizen describes as the rejection of fate and comments on how Ichigo Kurosaki's Bankai can easily get through Yammy's defenses. He also notes Ichigo's power fluctuation, which varies between very weak and stronger than his own.

It would appear that Ulquiorra and Grimmjow, the 6th Espada, are not on good terms. While Ulquiorra allows Yammy to kill anyone he deemed as "trash", which includes Ichigo, Ulquiorra allows him to live based on his belief that Ichigo's power is so turbulent that eventually he will destroy himself. Grimmjow's conflicting viewpoint is that Ichigo should be destroyed outright, as he can overcome his weakness and grow even stronger. Despite Grimmjow's argument, Aizen trusts Ulquiorra's judgment. This disagreement leads to Grimmjow's unauthorized assault on the real world. Though Ulquiorra is of a higher rank than Grimmjow, Grimmjow is confident that Ulquiorra is afraid to fight him for fear of them destroying one another.

Powers & Abilities
Ulquiorrra is the Cuarta Espada in Aizen's army, meaning Ulquiorra's abilities are fourth amongst all of the Arrancar under Aizen's command.

Cero: are high-powered energy blasts that can be fired from various body parts, he most commonly does from either his hand or fingers. His Cero is uncommon as its a unusual green color compared to the normal red.

Bala: The technique hardens the user's spiritual pressure and fires it like a bullet from their fist.

Hierro (鋼皮（イエロ）, Hiero; Spanish for "iron"): refers to the hardened skin of the Arrancar, which is a result of their compressed spiritual power. He can deflect attacks of similar power barehanded. He is able to fight Ichigo in his hollow form without unsheathing his sword, rendering Ichigo defenseless with two attacks and not sustaining injuries of any kind.

Enhanced Strength

Garganta (黒腔（ガルガンタ）, Garuganta; Spanish for "throat"): is how Arrancar move to and from Hueco Mundo. Ulquiorrra has the ability to use the technique. It literally tears open the dimensional fabric separating the worlds, revealing a tunnel of whirling, torrential energy that must be focused and solidified to create a discernible pathway. In the games, Ulquiorra uses this technique to generate make-shift vortices to draw opponents in, as well as teleport from place to place

Sonido Master

Instant Replay: Ulquiorra has the unusual ability to replay events he has seen to others by removing and crushing his left eye, which then turns into dust and flows around those Ulquiorra intends to use it on. The dust shows images of what Ulquiorra has seen during his missions. This eye apparently can regenerate, as Ulquiorra is seen with two eyes in his next appearance, and Yammy comments on it to that effect.

Hand-to-Hand Combatant

Spiritual Power

Zanpakutō
The name and released state of Ulquiorra's Zanpakutō have not been revealed, as he has never been shown using it, instead relying on his bare hands and steel skin. The handle is green and the guard has two curved extensions from its shorter sides, giving it an eye-like appearance. When Ichigo appears to confront him the second time, he is shown drawing his Zanpakutō, ready to duel.

Appearances in other media
Ulquiorra is the first arrancar to be featured in a Bleach video game, appearing in the Bleach: Heat the Soul 3 and Bleach: Heat the Soul 4 installments of the 'Bleach: Heat the Soul' series for the PlayStation Portable. He also appears in the Wii fighting game Bleach: Shattered Blade. He has a cameo and artwork in Bleach DS 2nd: Kokui Hirameku Requiem.

Ulquiorra has his own character album as part of the Bleach Beat Collection 3rd Session. The two vocal tracks are entitled CRUSH the "WORLD" DowN and Our World.

Trivia

 * He was recently voted the 10th most popular character in Bleach after receiving 3751 votes.
 * His first name comes from Patricia Urquiola, an architect, and his last from Father Hubert Schiffer, a survivor from the atomic bombing of Hiroshima, which is Tite Kubo's home town.
 * His name is possibly a reference to "El Que Llora" in Spanish, meaning "he who cries."
 * "Schiffer" means "boatman/sailor" in German