An Arrancar (破面（アランカル）, Arankaru?, Spanish for "to tear off," kanji translates as "broken mask") is a human-like Hollow with its Hollow mask almost completely removed. Arrancars have the powers of a Soul Reaper, including a weapon similar to a Zanpakutō, as well as strength, speed, and intelligence beyond the level of normal Hollows. In addition to these improvements, Arrancars also have hierro (鋼皮（イエロ）, iero?, Spanish for "iron," kanji translates as "steel skin") skin, hard enough to defend against swords to an extent. Arrancars use a technique known as sonido (響転（ソニード）, sonīdo?, Spanish for "sound," kanji translates as "moving sound") to travel at extremely high speeds across a short distance. Stronger Arrancars have been shown to possess relatively harder hierro or faster sonido among other abilities, either unique or based on common techniques, such as the several variants of the Cero technique.
Like Soul Reapers, all Arrancars possess a Zanpakutō (斬魄刀?, literally, "soul-cutting sword"). Unlike a Soul Reaper's, however, whose Zanpakutō is a manifestation of its owner's soul, an Arrancar's Zanpakutō is a manifestation of its former self. With occasional exceptions an Arrancar's Zanpakutō resembles a regular sword in its "sealed state." When "released" through a process called Resurrección (帰刃（レスレクシオン）, resurekushion?, Spanish for "resurrection," kanji translates as "returning blade"), the sword combines with and changes the appearance of the Arrancar. In most cases of Resurrección part of the Arrancar's original Hollow form is restored and the Arrancar is granted greater strength and access to his or her original abilities. Arrancars are able to discard or remove certain elements of their released forms to better focus their powers. This results, however, in the Arrancars losing those attributes permanently, comparable to ripping off one's limb.
Arrancars become major antagonists in Bleach during the second part of the series, as they are led by Sōsuke Aizen, who uses the hōgyoku to create and perfect the Arrancars. But after Vandenreich's conquest of Hueco Mundo, setting up the final part of the series, many of the Arrancars who survived Aizen's defeat were captured to be either drafted as soldiers or be killed. According to Tite Kubo, many of the Arrancars are named after real life architects and designers.
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