Gengorō's zanpakutō transformed the barren landscape of Hueco Mundo into a flourishing forest with a swift invocation of its Bankai, Yashin no Hakoniwa (野心の箱庭, Ambition's Garden). Towering trees with verdant leaves, dense underbrush, and vibrant flowers manifested, defying the desolation that defined Hueco Mundo. The sudden transformation not only provided a strategic advantage but also served as a testament to Gengorō's control over nature.
The lush forest became an extension of Gengorō's will. With a focused expression, he directed the trees to entwine their roots and ensnare the encroaching hollows. The roots, imbued with spiritual energy, responded to Gengorō's commands, creating a defensive barrier that slowed down the relentless advance of the hollow horde.
Simultaneously, Gengorō harnessed the power of Yashin no Hakoniwa to orchestrate an intricate dance of flora. Flowers of various hues burst into bloom, releasing a mesmerizing display of petals. However, these petals were not mere adornments; they carried a potent pollen with bewildering effects.
As the pollen dispersed through the air, the hollows, already driven by instinct and aggression, fell prey to confusion. The intoxicating fragrance of the flowers clouded their perception, leading them into a state of disarray. In their bewildered state, the hollows turned on each other, their frenzied attacks contributing to the chaos within their own ranks.
Yet, the extraordinary power of Yashin no Hakoniwa came at a cost. In the world of Hueco Mundo, where life struggled to exist, the lush forest created by Gengorō's Bankai was an anomaly. The vibrant greenery thrived on Gengorō's reiryoku, which was continuously drained to sustain the unnatural environment.
As Gengorō manipulated the plants to defend against the hollow onslaught, he felt the strain of the constant reiryoku drain. Beads of sweat formed on his forehead, a testament to the immense effort required to maintain the ability Nature's Garden amidst the desolate environment of Hueco Mundo.
In the midst of the forest's bloom, Kensei seized the opportunity to recover. The slowed advance of the hollows provided a brief respite, allowing Kensei to catch his breath. He stood up and slammed his fist covered by his zanpakutō, Tekken Tachikaze together, gathering his strength for the inevitable continuation of the battle.
Rin, observing the coordinated efforts of his fellow instructors, redoubled his focus on opening the gateway back to the Soul Society. The delicate process required precise incantations and spiritual energy manipulation, a task made more challenging by the constant distraction of the student screaming and worrying along with the sounds of battle.
Gengorō, sensing the impending strain on his reiryoku, knew that the time bought by Yashin no Hakoniwa was crucial. He directed the trees to form an encirclement around Kensei, a green energy then flowed from them entering Kensei's body. Whatever this was, Kensei could feel his strength rapidly returning.
However, the delicate balance teetered on the edge. The strain on Gengorō's reiryoku became more apparent as the vibrant forest showed signs of withering. The leaves began to lose their luster, and the once lush landscape started to fade.
Gengorō, determined to hold the line, shouted to Kensei, "Get ready, Kensei! We'll need to make our move soon!"
Kensei, reinvigorated but mindful of the ongoing battle, nodded in acknowledgment. The temporary respite offered by Gengorō's Ambition's Garden allowed him to regain enough stamina for the impending clash.
As the vibrant forest showed signs of withering, Gengorō sensed the pressing need to retreat. The once-lush greenery began to fade, and the trees that had served as a defensive barrier withdrew their roots. Beads of sweat dripped down Gengorō's face as he redirected the remaining energy back into his zanpakutō. The green energy flowed from the trees into his blade, and with a swift motion, Gengorō disengaged his Bankai.
"Kensei switch! I can't sustain this any longer," Gengorō shouted, his voice strained from the exertion.
Kensei, fueled by the returned strength from Gengorō's mysterious energy transfer, roared and charged at the hollows. His iron gauntlets slammed into the horde, tearing through the ranks and creating a path through the encroaching threat. The hollows, confused and disoriented by the remaining effects of Yashin no Hakoniwa, struggled to organize a coherent counterattack.
In the midst of the chaotic clash, Gengorō retreated towards Rin, who remained focused on the complex incantations needed to open the gateway back to the Soul Society. Gengorō's breaths were heavy as he reached Rin's side.
"Rin, how's the gateway? We can't hold them off for much longer," Gengorō questioned, urgency evident in his tone.
Rin, beads of sweat on his brow, replied without diverting his concentration, "It's almost there. Just a little more, Instructor Ōnabara."
Gengorō turned toward the gathered students, their faces reflecting a mixture of fear and despair. He raised his voice to address them, "Listen up! This is what you've been training for. We're in the middle of a fight for survival. You've got to protect yourselves and Rin. Instructor Muguruma and I will do what we can, but you can't rely on us alone."
A murmur of acknowledgment spread among the students as they tightened their grips on their zanpakutōs. Gengorō could feel the approach of a more significant threat, and he scanned the surroundings with a heightened sense.
"Kensei pull back and conserve your strength we've got incoming. Four powerful hollows most likely Vasto Lordes are heading our way. You students brace yourselves!" Gengorō announced, the gravity of the situation hanging in the air.
Kensei, having carved a temporary path through the hollows, joined Gengorō and Rin. The instructors formed a defensive line alongside the students, who prepared for the approaching onslaught.
The air crackled with tension as the instructors and students felt the reiatsu of the approaching Vasto Lordes. Before they could even be seen one of them fired a Cero at the group.
Kensei with cold sweat jumped forward and reacted swiftly. With a burst of speed, he lunged forward, his right fist infused with reiryoku. The Cero, a powerful energy blast fired by the approaching Vasto Lorde, hurtled toward the group.
Kensei intercepted the blast, the collision between his reiryoku-infused fist and the Cero creating a burst of energy that sent shockwaves through the surroundings. The ground beneath him trembled as the force of the impact pushed him back, but he stood firm, managing to divert the lethal blast away from the group.