Espada

The  are the top-ranked Arrancar in Aizen's army of Arrancar and are the primary antagonists of the series.

Outline
The Espada are regarded as the strongest Arrancar in existence. At the time of the group's introduction it consists of nine males and one female. Each Espada member is chosen for their superior combat ability and then assigned a number from 1 to 10 that indicates their rank and relative power level, which is tattooed somewhere on their body (Grimmjow's is on his lower back, for instance).

The Espada are given free control over the Números and may choose as many of them as they like to become their Fracción. Similar to the power gap between captains and lieutenants in the Gotei 13, the strength of the Espada far surpasses that of the average Número. Aizen himself is confident enough of his Espada's abilities to send them out on potentially hazardous missions, such as gathering information in the real world, fighting Shinigami captains inside Las Noches and Karakura Town by themselves, and gathering the Vasto Lorde.

Being Aizen's most direct subordinates (not counting Gin Ichimaru and Kaname Tōsen), the Espada are privy to several of Aizen's plans and most intimate secrets, such as his goals of destroying Karakura Town and creating the King's Key, the location of the Orb of Distortion within Las Noches, and the name and illusory abilities of his Zanpakutō. Aizen's respect for the Espada's abilities is reflected on his manner of addressing them, often referring to them as "my dear Espada" and sitting at the head of the same table with them while discussing the events around Hueco Mundo.

As Aaroniero Arruruerie notes, all of the Espada except him were at least adjuchas-class menos before becoming arrancar.

History
While it is not specified when the Espada were first created as a group, it is implied that the original Espada were already in existence sometime before Aizen's defection from Soul Society and acquisition of the Hōgyoku. Since then, the composition of the Espada has changed, reflecting a change in membership and position. Before his death, Aaroniero Arruruerie was the sole member of the current Espada who was also part of the first-generation Espada.

Ranks
Unknown: Barragan Luisenbarn, Stark, Halibel

4th: Ulquiorra Schiffer

5th: Nnoitra Jiruga (Deceased)

6th: Grimmjow Jeagerjaques (Status unknown)

7th: Zommari Leroux (Deceased)

8th: Szayel Aporro Granz (Deceased)

9th: Aaroniero Arruruerie (Deceased)

10th: Yammy

Former Espada
These are the Espada that have either died or left Las Noches and did not become part of the Privaron Espada.
 * Neliel Tu Oderschvank - Former 3rd
 * Luppi - Temporary 6th (Deceased)

Demotion
An Espada may be demoted from the Espada, such as Grimmjow Jeagerjaques when his left arm was cut off by Kaname Tōsen. In most cases they will be demoted to the, who are former Espada that have officially lost their rank and are assigned a three-digit number.

Privaron Espada
The Privaron (Spanish: deprived) are former Espada who have officially lost their rank and are assigned a three-digit number. Being former Espada, they are far stronger than the normal Números. They reside in Tres Cifras, which translates literally from Spanish as "three digits". As mentioned by Dordonii, these former "naturally created" Espada were rendered obsolete after Aizen began artificially creating arrancar to meet his own standards. It may be that the Privaron Espada numbers are simply their old number turned into a three digit one. (Ex. Dordonii was the 103rd and he may have been the 3rd in the original Espada)


 * Dordonii Alessandro Del Socacchio - The 103rd (Deceased)
 * Cirucci Thunderwitch - The 105th (Deceased)
 * Gantenbainne Mosqueda - The 107th

Devices and Technique

 * Caja Negación is used to punish Arrancar subordinates by trapping them eternally in an alternate dimension. However, should the Caja Negación be used on an Espada, the Espada will eventually break out of the alternate dimension (usually within a few hours), due to their large amount of Reiatsu.


 * Cero: Like any other Hollows, they can use this blast.


 * is an Arrancar alternative to the Cero. The technique hardens the user's spiritual pressure and fires it like a bullet from their fist. Though somewhat weaker than a Cero blast, it moves about twenty times much faster than a Cero and can be fired at a much higher rate. This technique was first demonstrated by Wonderwice Margera against Kisuke Urahara, and elaborated upon by Yammy during the same battle.


 * Gran Rey Cero: (王虚の閃光, グラン・レイ・セロ;Spanish for "grand king zero") is a particular, very strong Cero. To perform this potent variation of the Cero, the Arrancar first draws blood from the Cero-generating appendage using his or her zanpakuto, then charges the Cero while mixing the blood with it. The result is a Cero with a much greater attack power and speed, as well as a change of color unique to the Espada. This attack was first used by Grimmjow Jeagerjaques in order to incite Ichigo Kurosaki into donning his Hollow mask. Grimmjow refers to it as "the ultimate cero", as Gran Rey Cero is apparently a result of Shinigami-Hollow hybridization (both arrancar blood and a zanpakuto is required to use this technique). Grimmjow is, to date, the only Arrancar that has ever used Gran Rey Cero and Caja Negacion on-screen.


 * is how Arrancar move to and from Hueco Mundo. Kaname Tōsen and Kisuke Urahara have also demonstrated 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.


 * refers to the hardened skin of the Arrancar, which is a result of their compressed spiritual power. While their skin is strong enough to block even released Zanpakutō bare-handed, it is by no means impenetrable. Stronger Arrancar have proportionally stronger skin. Nnoitra Jiruga claims his Hierro is toughest amongst the Espada.


 * is the Arrancar equivalent of the Shinigami ability to sense Spiritual Pressure. It functions similar to a sonar. Using pesquisa requires most Espada to enter a meditative state; however, Nnoitra Jiruga has a variation of this technique that involves placing his fingers to the ground to determine an opponent's approximate location as well as the amount of Spiritual Pressure an opponent has.
 * is the Arrancar equivalent of the Shinigami flash steps and the Quincy Hirenkyaku; it allows the user to travel at incredibly high speeds for short distances. Use of Sonído is punctuated by a brief static sound, in contrast to the "swish" sound used for Flash Steps. Zommari Leroux claims that his Sonído is the fastest amongst the Espada.

Current events
Currently, the Espada have lost four members (excluding Luppi, Grimmjow's temporary replacement);
 * Aaroneiro Arruruerie was killed by Rukia Kuchiki;
 * Szayel Aporro Granz was killed by Mayuri Kurotsuchi;
 * Zommari Leroux was killed by Byakuya Kuchiki;
 * Nnoitra Jiruga was killed by Kenpachi Zaraki.
 * Grimmjow Jaegerjaques was incapacitated by Nnoitra Jiruga.
 * Yammy's location is unknown.
 * Ulquiorra was left in charge of Las Noches while Aizen, Tōsen and Ichimaru, along with Stark, Barragan and Halibel (the top three Espada) and their Fracción, battle the Gotei 13 in the fake Karakura Town.

Shinigami Counterparts
Several of the Espada are very similar to certain shinigami by either their roles, personalities, abilities, or relative power level. However, they're not exactly and completely the same.


 * Barragan - Shigekuni Yamamoto-Genryūsai: are old and have a measure of authority, but Barragan, unlike General Yamamoto, who is humble self-assured, and confident, Barragan is arrogant, overconfident, also somewhat foolhardy and egotistical, as his fraccions called him "God".
 * Halibel - Soifon: are calm, reserved, and analytical. However, unlike Soifon, Halibel is barely and yet to be seen using her power.
 * Stark - Shunsui Kyōraku: are lazy, laid-back, easy-going, honorable, bear similar facial features, and are powerful combatants.
 * Ulquiorra Schiffer - Tōshirō Hitsugaya: both said to be cold to others. Also known not to talk much, except unlike Hitsugaya, Ulquiorra is indifferent, as he is known to stab people in where his hole is located on, and never had feelings.
 * Nnoitra Jiruga - Kenpachi Zaraki: use brute force in combat, wear eyepatches, and have an overly violent lust for battle. However, unlike Kenpachi, he is very lecherous.
 * Grimmjow Jeagerjaques - Ichigo Kurosaki: are short-tempered, stubborn, reckless, rude, impulsive, persistent, resourceful, analytical, have an apparent habit of cheating death more than once, and are equally powerful combatants with a twisted sense of honor. However, unlike Ichigo, who fights for his friends, allies, and family, Grimmjow fights for his very own benefits.
 * Zommari LeRoux - Byakuya Kuchiki: use speed in their combat, sonído and shunpo respectively, and are generally silent, calm, somewhat overconfident, and have a small measure of pride, often refusing to accept defeat. However, unlike Byakuya, Zommari tends to brag about his Gémelos Sonído being the "fastest of all Espadas".
 * Szayel Aporro Granz - Mayuri Kurotsuchi: are scientists and are cruel to both their enemies and their allies/minions. However, unlike Mayuri, he tends to think highly and condescendingly of himself and wishes to see all non-Hollows to be totally wiped out of existence.
 * Aaroniero Arruruerie - Jūshirō Ukitake: opposites, both dealing with Rukia Kuchiki.
 * Yammy - Sajin Komamura: are the biggest in their groups and use pure strength. However, unlike Sajin Komamura, Yammy is somewhat oafish and is portrayed as arrogant in his abilities.
 * Nel Tu - Retsu Unohana: can heal and also Nnoitra Jiruga doesn't like Nel Tu and Division 11 doesn't like Division 4.
 * Luppi - Rukia Kuchiki: Both of them look alike (not quite, though), are powerful, and were replaced by Grimmjow and Ichigo.

Trivia

 * Interestingly enough,Yammy introduces himself as "Espada Dies, Yammy!" (Espada 10, Yammy! in Spanish) when he fights Captain Hitsugaya during their mission to kidnap Orihime Inoue, whereas all other Espada introduce themself with XXth numbers. This may be a mistake on Tite Kubo's part or Yammy is just a special case.


 * It is higly implied by fans, due to the fact that it needs much Spiritual Energy, is hard to use and only an Espada used it; that the Gran Ray Cero is an Espada-exclusive Cero, although that there is actually no proof.