Yasutora Sado vs. Gantenbainne Mosqueda

 is a battle taking place during the Invasion of Hueco Mundo between Yasutora Sado and Arrancar #107. Gantenbainne Mosqueda, acting as the catalyst for the former to finally awaken the true form of his Fullbring.

Prelude
After Yasutora Sado enters Las Noches alongside his friends, they reach a crossroads with five different exits and strong Reiatsu emanating from the paths ahead. At Rukia Kuchiki's behest, the five of them split up and each take a different exit. Soon afterward, in a dark room filled with square holes in the ground, Sado is confronted by Gantenbainne Mosqueda.

Battle
Soon afterward, Sado finds himself struggling against Gantenbainne and is sent crashing through a wall, where he is embedded in another wall on the far side of the room as Gantenbainne walks through the hole and observes that he is no match for Arrancar #107. Having already manifested his Fullbring, Brazo Derecha de Gigante, Sado channels energy into it and leaps toward Gantenbainne, only for the latter to move to him in midair with Sonído, grab him by the head, and declare that a Human who cannot even perform high-speed movement has no chance of catching him prior to throwing Sado into the ground and wondering how many times he must tell the latter this.

In turn, a sweating Sado gets to his feet and channels energy into Brazo Derecha de Gigante again to throw a punch aimed at Gantenbainne's head. Despite this, Gantenbainne easily evades it and initiates Uno Dos Cientos with his Zanpakutō gauntlets by first punching Sado hard in the stomach, then unleashing a barrage of punches across his body that leaves him coughing up blood before delivering a powerful downward punch that shakes the entire room and embeds Sado face-down in the ground. In the aftermath, Gantenbainne tells Sado to get up and reveals that he knows the latter is still hiding his true strength. Performing the sign of the cross on himself, Gantenbainne chastises Sado for concealing his abilities like this and suggests that they have an honest fight, but when Sado remains unresponsive, Gantenbainne states that his heart is broken and channels energy between the two prongs of his left gauntlet.

However, upon being attacked by Gantenbainne, Sado senses something about his right arm change and gets up just in time to block the attack as he apologizes to Gantenbainne and details how he was not trying to hide it, but has instead felt something strange ever since he came to Hueco Mundo and was initially confused by it to the point where he had to struggle to control it. After concluding that he finally has and can now fight Gantenbainne with everything he has got, Sado emerges from the dust cloud with the final form of Brazo Derecha de Gigante, a large shield emerging from his forearm that he identifies as his real right arm. Stepping forward, Sado tells a stunned Gantenbainne that he did not realize until now, perhaps intentionally, that he felt his power stirring upon coming to Hueco Mundo in a manner that it did not when he visited Soul Society, with it growing stronger as he got closer to this place until it finally calmed down when Gantenbainne hit him for the first time. Sado theorizes that this stirring was excitement and that his power was longing to come home.

As he continues approaching Gantenbainne and compares the former's attack to a rough welcome from a countryman that caused his power to remember what it was, Sado admits to wondering about the nature of his power ever since he acquired it because it is not like that of a Shinigami or Quincy, and after revealing it is more akin to the power of a Hollow, Sado names Brazo Derecha de Gigante as his right arm's true form and true power before firing a stronger El Directo blast at Gantenbainne, who is sent crashing through the far wall and out into a hallway as blood pours down his face. Upon skidding to a halt, Gantenbainne sees Sado stepping out of the hole in the wall and moves to kick him with Sonído, but Sado casually intercepts his kick with Brazo Derecha de Gigante and asks Gantenbainne if he slowed down.

With Sado sending Gantenbainne flying with a swipe of his arm, the latter lands on a nearby wall and is caught off-guard by Sado leaping toward him in the time it takes for him to look at his foot and back, resulting in Sado throwing a punch with explosive force that destroys the upper part of the column Gantenbainne was located near. While leaping out of the resulting dust cloud, Gantenbainne frantically questions where Sado got this power from and how his response time to Sonído has increased so much, only to be startled when Sado appears behind him in midair and charges another El Directo on Brazo Derecha de Gigante, which Gantenbainne realizes he cannot block just before Sado fires a massive blast of energy that engulfs him.

In the aftermath, Sado approaches the area where Gantenbainne landed as the latter admits that Sado was not kidding about using his true power, only to remind Sado that he has a true form too and emerge from the dust cloud with his Resurrección, Dragra, activated. After pulling down his visor, Gantenbainne holds out his fists together in front of him, asks God for forgiveness, and fires a massive blast of energy at a shocked Sado, leveling the surrounding area in the process. However, in the clearing dust, Gantenbainne raises his visor in astonishment when Sado apologizes to him for forgetting to mention something earlier. Clarifying that Brazo Derecha de Gigante is the true form of his right arm where Oscar Joaquín de la Rosa's soul dwells, as Oscar taught him to use his power to protect people and consequently concentrated his defensive power into his right arm, Sado reveals that he was able to unlock his offensive power through his training and displays his left arm, which has manifested the other half of his Fullbring, Brazo Izquierda del Diablo, as white armor with a spike protrusion on his shoulder that represents his offensive power. An initially stunned Gantenbainne laughs nervously at this and claims that the name sounds sinister as he charges up two energy spheres in front of his hands, combines them, and fires Rugir del Dragón at Sado. However, Sado simply grabs the projectile with his left hand, stopping it in midair as its energy erratically careens around him during its dispersal, and begins calmly approaching a sweating Gantenbainne, who roars and runs forward while throwing an energy-infused uppercut. In response, Sado effortlessly blocks the blow with Brazo Derecha de Gigante and holds out Brazo Izquierda del Diablo, which begins crackling with energy at its fingertips as Sado clenches his fingers into a fist and performs La Muerte, delivering a powerful blow to Gantenbainne that completely shatters Dragra and imprints a large and fearsome skull onto the wall behind him.

Aftermath
The force of Sado's blow destroys the wall and sends a near-unconscious Gantenbainne flying onto the sands outside, where Sado, having sealed both halves of his Fullbring, kneels at the former's side and observes that he only discovered his power because Gantenbainne's attack was so ferocious. Thanking Gantenbainne for helping make him stronger than ever before, Sado promises to not kill him and wishes Gantenbainne well while standing up to depart, only to see a sunny blue sky above him and wonder if he is not within the walls of the dome after all since he cannot see the ceiling of the dome that he observed upon entering Hueco Mundo.

Though Sado is left ruminating on the sunlight not making sense because Hueco Mundo is a land of perpetual darkness with an unmoving moon, he is alerted when an alarmed Gantenbainne tells him to run and turns around to see Nnoitra Gilga standing between them with his massive Zanpakutō slung over his shoulder. Despite Gantenbainne frantically urging him to run away, Sado manifests Brazo Derecha de Gigante once again and observes that Nnoitra is not attacking him despite being visibly strong. Not wanting to find out what Nnoitra can do by waiting, Sado manifests Brazo Izquierda del Diablo as well and resolves to finish this in one blow before slamming his energy-imbued left fist hard into Nnoitra's chest. However, a grinning Nnoitra remains completely unharmed and questions if this is all a shocked Sado has got before slashing Sado diagonally across the chest, which severs a large chunk of Brazo Derecha de Gigante and causes a stunned Sado collapses in a shower of blood as a disappointed Nnoitra observes that he knew Sado would be weak.

Moments later, Nnoitra sits on a bent tree as he uses Indice Radar, where he is greeted by his Fracción, Tesra Lindocruz. Approaching Nnoitra from behind, Tesra notices Sado lying face-down in the sand nearby and observes that Nnoitra has not finished him off yet, prompting Nnoitra to confirm this and question who would be impressed by him killing a thousand pests like Sado since there is no profit in squashing bugs. Suddenly, Nnoitra senses Aaroniero confronting Rukia and gets up to seek out the source of an enormous Reiatsu he has just detected so he can crush it, but is interrupted when Sado gets up behind him with Brazo Izquierda del Diablo activated and refuses to let Nnoitra do so.

Though Nnoitra grins and prepares to battle as Sado rushes toward him, Tesra moves between them at the last second and blocks Sado's punch with Plato Colmillo as he disparages Sado for attacking Nnoitra in his condition, leaving the latter to curse as he collapses once more. While Tesra sheathes his Zanpakutō and asks Nnoitra if they should go now, Nnoitra holds the edge of his own Zanpakutō diagonally across Tesra's upper body and questions why Tesra believed Nnoitra needed his help, prompting Tesra to note all of Sado's remaining power was in that blow. However, Nnoitra asserts that it would not have reached or injured him regardless and warns Tesra to never forget that no one can break his body because he is the Espada's best.