Wonderweiss Margela

is the only modified Arrancar in Sōsuke Aizen's army. Though not an Espada, Soul Society ranks his Spiritual Energy in the same class as them.

Appearance
Wonderweiss has a thin and somewhat child-like body. He has light blond hair, parted to one side, with the tips fanning out from his face. The remains of his Hollow mask consist a three-point tiara on the top of his head. He wears the Arrancar jacket with a hole in the middle of his chest, revealing his Hollow hole and the tip of a mark on his chest. The outfit also has large arm cuffs on the sleeves. He only has two teeth visible when smiling, freckles and bright purple eyes.

Even though his body was wrapped in bandages during his birth, with several protrusions throughout his body, as a Hollow, he is roughly humanoid in both size and shape.

Personality
Wonderweiss's personality is very childlike and possibly comparable to a child with autism; for example, when sent on a mission to kill, he instead played around with a dragonfly. He shows some hostility, firing a defensive Bala blast at one point, but quickly reverts back to his usual childlike state after doing so. In a later confrontation, Wonderweiss displays a higher level of hostility by stabbing Ukitake through the chest without any warning or provocation. Despite his childlike demeanor, he also displays some compassion by freeing Tia Harribel.

Wonderweiss does not speak in coherent sentences, only saying a few syllables at a time such as an infant would. The only coherent phrase he ever speaks is his own name, immediately after being "reborn" as an Arrancar. Kaname Tōsen remarks that Wonderweiss, like himself, is a pure being (though he remarks he doesn't quite know what exactly is pure about him) who often tend to stick together; he claims this is why Wonderweiss follows him everywhere. It is implied that he tried to restrain Gin Ichimaru from approaching Tōsen because Wonderweiss was wary of him.

Arrancar arc
Wonderweiss' first appearance occurs during his actual creation by Aizen; his original form is seen wrapped in what appears to be bandages while a barrier surrounds his body. Numerous Espada were present at his "birth", including Coyote Starrk, Tia Harribel, Ulquiorra Cifer, Nnoitra Jiruga, Luppi (still instated as an Espada at the time), Grimmjow Jaegerjaquez, Aaroniero Arruruerie, and Yammy Riyalgo.

Wonderweiss was among the Arrancar present during the third invasion of Karakura Town, where comments made by Soul Society scientists suggest that his reiatsu is at a similar level to an Espada. However, he spend most of the invasion waiting, amusing himself and playing, waiting for their mission to be over. This was until Kisuke Urahara intervened in Luppi's fight, causing Wonderweiss to attack with unforeseen ferocity. This can be explained by the boy's sudden interest in Kisuke's hat. He only relents upon seeing his power emanate from his hand, intriguing him completely and ending his fight with the former captain. Kisuke noted that he was confused on whether he should attack him or not, since he was very powerful, but also seemingly innocent. Yammy Riyalgo then picks up the fight where Wonderweiss left off. He is pulled back to Hueco Mundo via Negación once Ulquiorra Cifer completes his mission.

Ulquiorra brings the Human Orihime Inoue to Hueco Mundo, and she is greeted by Aizen, who has her restore Grimmjow Jaegerjaquez's arm as a demonstration of her power. Wonderweiss serves as a witness to this and Grimmjow subsequently impaling Luppi with his restored arm (and power), simultaneously killing him and regaining his former rank.

Hueco Mundo arc
When Ichigo Kurosaki, Uryū Ishida, Yasutora Sado, Renji Abarai, and Rukia Kuchiki invade Hueco Mundo, Wonderweiss is with Kaname Tōsen, who is monitoring the intruders' activities. When Gin Ichimaru walks in, Wonderweiss stops him, due to feeling uneasy about him. Kaname explains that he believes Wonderweiss is a pure being, which is why he follows Kaname (although he admits that he doesn't know if Wonderweiss is pure good or pure evil).

Fake Karakura Town arc
Wonderweiss arrives in the Fake Karakura Town through an extremely large Garganta, interrupting the battle between the Primera Espada Coyote Starrk and Captains Shunsui Kyōraku and Jūshirō Ukitake, which surprises Starrk. Wonderweiss is accompanied by Fūrā, a Hollow so massive that it literally has Gillian masks for nails. Captain Sajin Komamura realizes that it is the same creature seen looming over the numerous Gillian who created the Negación that transported Aizen, Gin, and Kaname from Soul Society to Hueco Mundo at the end of the Soul Society arc.

Immediately after arriving, Wonderweiss suddenly appears behind Jūshirō and impales him with his own hand, injuring the captain and causing him to fall towards the buildings below. Shunsui attempts to attack Wonderweiss, but is hit in the back by an opportunistic Cero from Starrk sending him towards the ground with Jūshirō. Starrk comments that the arrival of Wonderweiss means that Aizen has grown tired of the battle. Wonderweiss then lets out a battlecry which seems to break Hitsugaya's ice obelisk, freeing Harribel. The cry also seems to "blow" away the smoke left after Soifon's Bankai attack on Baraggan, revealing that the attack had no effect on him. Wonderweiss continued to scream and Fūrā vomited many Gillian-class Menos from its opening to confront the Vizard. When the Vizard Mashiro Kuna attacks his companion, Wonderweiss simply stares at her. Shocked at seeing his companion die, Wonderweiss then charges his Cero from his mouth but before he can fire it, Mashiro kicks him in the face. He is later seen lying on the ground with Mashiro shouting "Yay! Victory!"

Later, Wonderweiss attacks Mashiro from the ground, but his attack is blocked and he is kicked away. Mashiro fires a Cero at Wonderweiss, which he successfully counters with his battlecry. Shortly afterwards, Mashiro's mask suddenly shatters and Wonderweiss punches her directly in the face, rendering her unconscious. He is about to hit her again but his fist is blocked by Kensei, who says that he's not the type to go easy on kids, before he then proceeds to throw Wonderweiss, sending him flying down into the buildings below. As Kensei and Mashiro continue their discussion, Wonderweiss quickly recovers and approaches Kensei, provoking him into releasing his Bankai and the two face off, resulting in a huge explosion.

Wonderweiss later appears behind Genryūsai Shigekuni Yamamoto (with the outcome of his fight with Kensei unknown) in his Resurrección state, nullifying the abilities of his Ryūjin Jakka as Aizen bids Yamamoto farewell.

Powers & Abilities
Although his true strength has yet to be seen, Wonderweiss is shown to have strength on par with the Espada, being counted as one by the Soul Society, and being sent on mission with others. The fact that he could sneak up on Jūshirō Ukitake, one of Soul Society's most capable and powerful captains, and seriously wound him with one strike and destroy Hitsugaya's huge ice obelisk with a simple cry gives hint of his actual power. Even Starrk, the Primera Espada, said if Wonderweiss is in battle, Aizen is wanting to end the fight, further hinting on the Arrancar's powers.

Immense/Vast Spiritual Power: All of the Arrancar invading Karakura during Ulquiorra's mission to capture Orihime Inoue were stated by 12th Division observers (using spiritual power measuring sensors) to be Espada level. Being one of these Arrancar, this means that Wonderweiss has at least similar spiritual power to the Espada, despite not being one himself.



Cero: Like other Arrancar, Wonderweiss fires his Cero through his mouth. It's full potential hasn't been shown as Mashiro extinguishes his Cero while he is charging it.

Bala: This technique hardens the users spiritual pressure and fires it from their fist like a bullet. The power emanating from his hand after his attack was pink and static-like, signifying his Bala is pink.

Sonído Master: The Arrancar equivalent to Flash Step. Wonderweiss was able to sneak up on Kisuke, a former Captain, and attack him with a Bala, signifying his speed and use of Sonído. He later instantly appears behind Ukitake before the captain could react, again showing his masterful abilities with Sonído.

Expert Hand-to-Hand Combatant: During battle, Wonderweiss relies primarily on his fists. He has defeated Mashiro, a Vizard who is also an expert hand-to-hand combatant.

Garganta: A method Hollows use to move from Hueco Mundo into the Human World. It tears the dimensional space and reveals a portal of whirling energy. Wonderweiss is able to move between worlds using this technique.

Hierro: Wonderweiss' Hierro is shown to be very strong being able to pierce Ukitake's chest with ease.

Enhanced Strength: Wonderweiss must have a considerably amount of strength being able to critically injuring Mashiiro with one punch.

Enhanced Durability: Wonderweiss has shown to be a very tough and determined fighter, repeatedly getting up to attack after being pummelled.

Enhanced Voice: Wonderweiss can even emit a loud battle cry that shattered Hitsugaya's ice obelisk, as well as countering Mashiro's Cero.

Hollow Control: With his battle cries he seems to be able to control Fūrā; as Tōsen said, "his words have meaning."

Zanpakutō

 * In its sealed state, Wonderweiss' Zanpakutō is a large purple sword strapped to his back, about as tall as he is. The hilt resembles a western long sword rather than the more common katana, although the familiar hilt weaving is present, whilst the guard resembles an Egyptian eye. From a back view the sheath represents a zweihander or claymore.


 * Resurrección: The release command is unknown. After releasing, Wonderweiss becomes a somewhat mutated version of himself. His shoulders and thighs grow significantly larger, with the shoulders popping out upwards. His arms and legs are also altered in size, being much skinnier than before. There are five holes in his abdomen, with two or three lines within each hole, except the middle. His face is covered from the upper half by a tall mask with three small horns, which seems to make his eye sockets hollow.


 * Resurrección Special Ability: As the only modified Arrancar in existence, Wonderweiss was made with the sole purpose of nullifying Genryūsai Shigekuni Yamamoto's Zanpakutō abilities.


 * Enhanced Hierro: After releasing, his Hierro becomes much stronger, as he was able to catch Yamamoto's blow with ease.

Trivia

 * When Wonderweiss impaled Jūshirō Ukitake, he stabbed him with his left hand but his right hand was shown being removed from his back and covered with blood.
 * Wonderweiss has a strange mark on his chest, directly below his Hollow hole.