Using strength to counter technique!
Since his speed was unmatched, Aizen didn't stubbornly try to fight with his own weakness against his opponent's strength. Instead, he chose to use overwhelming force to break through intricate techniques.
Besides Kyoka Suigetsu's hypnosis and Kido, Aizen's most outstanding trait was his immensely powerful Reiatsu. This was also why Yhwach included Aizen as one of the [Five Special War Powers].
While Toshiro held the advantage in speed, in terms of Reiatsu, even though Toshiro had reached the pinnacle of the beyond Captain-level, he felt the gap between them was still considerable compared to Aizen.
Thus, the wind pressure generated by Aizen's formidable strength directly shattered Toshiro's sword lights coming from all directions.
Seeing this, Toshiro couldn't help but frown slightly, thinking to himself: 'Although my strength has progressed rapidly over the years, it seems my current power still isn't enough to defeat Aizen.'
'Since I can't defeat Aizen now, I'll abandon all reservations and fight with everything I have! This time, I must force Aizen to use his full strength and see how big the gap still is!'
In their last battle in Hueco Mundo, Aizen had completely suppressed Toshiro without even fighting seriously, giving Toshiro a feeling of unfathomable depth.
This time, although Aizen still held the advantage, he didn't seem as effortlessly composed as before. If Toshiro went all out, Aizen would have no choice but to use his full strength to defeat him.
Thinking this, Toshiro no longer hesitated. His expression turned grave and serious.
Immediately, Toshiro chanted clearly: "Sit Upon the Frozen Heavens, Hyorinmaru!"
Boom! Boom! Boom!
Pillars of ice-blue Reiatsu shot into the sky. The already rainy, cloud-covered sky darkened further, giving a feeling of impending doom, like dark clouds pressing down on a city about to crumble.
Rumble!
Lightning flashed and thunder rumbled within the dark clouds, illuminating the originally gloomy night.
"Roar!"
Following a deafening dragon's roar, a frost dragon dozens of meters long materialized, coiling and swirling around Toshiro.
Standing proudly in the sky, Toshiro felt stronger than ever before during Shikai, even stronger than when he used his immature Bankai before reaching the beyond Captain-level.
This wasn't solely due to Toshiro reaching the pinnacle of beyond Captain-level and his increased Reiatsu. Part of the reason was the weather.
Because it was raining heavily, the air was filled with moist water vapor everywhere, allowing Toshiro to exert far more power than under normal conditions. Even the manifested frost dragon was a size larger than usual.
Moreover, it wasn't just the frost dragon. As long as there was sufficient moisture, the power of any of Toshiro's techniques would be significantly stronger than normal.
At this moment, Aizen, not far from Toshiro, frowned slightly. 'Shikai? But... this imposing aura... seems much stronger than usual?'
Regarding Toshiro's Shikai, Aizen had witnessed it before and it didn't have this level of majesty. While Shikai power increases with training, Aizen felt Toshiro's current Shikai power had increased far beyond the normal range.
'Is it because of the rain?' Aizen glanced at the continuous downpour.
'This is somewhat troublesome indeed,' Aizen thought to himself.
Before Aizen could finish his thought, Toshiro's attack was already upon him.
The blue frost dragon charged towards Aizen with an overwhelming, destructive momentum, as if aiming to annihilate him outright.
As the frost dragon charged, raindrops falling from the sky froze before even getting close, transforming into hailstones the size of a baby's fist that pelted the ground.
Faced with Toshiro's fierce assault, Aizen didn't meet it head-on but chose to retreat.
Aizen's figure flashed repeatedly, continuously evading the frost dragon's successive assaults.
Seeing this, Toshiro pointed Hyorinmaru at Aizen from a distance and chanted lightly:
"Weather Subjugation: Air Restriction!"
As Toshiro's words fell, Aizen's continuously evading figure suddenly stalled for an instant.
Weather Subjugation granted dominion over the sky. Weather Subjugation: Air Restriction was a technique Toshiro developed, using his sky dominion to repel and restrain enemies in the air.
Although the stronger the enemy, the lesser the effect, Aizen had never seen this move before. Caught off guard, he was inevitably affected.
Although Aizen's strength was immense, allowing him to quickly break free, his movement unavoidably halted for a split second.
In a battle between masters, a split second could determine many things.
The moment Aizen's figure stalled, Toshiro's frost dragon immediately seized the opportunity and charged at Aizen.
By the time Aizen reacted, it was too late to evade.
Seeing the situation, Aizen ceased dodging and chose to confront it head-on.
Aizen concentrated his vast, surging Reiatsu into his Zanpakuto, then unleashed a powerful Kenatsu slash towards Toshiro's frost dragon.
Boom!
Aizen's Kenatsu collided with Toshiro's frost dragon, producing a tremendous roar.
However, although Aizen's Kenatsu was powerful, it didn't shatter Toshiro's frost dragon.
After Aizen's Kenatsu was neutralized, the heavily damaged frost dragon, its surface covered in cracks, stubbornly continued its assault on Aizen.
Unable to launch another attack in time, Aizen could only raise his sword horizontally to block.
Boom!
Under the powerful impact, Aizen's body was forced backward continuously.
Crackle, crackle, crackle—!!
A freezing sound erupted. The Zanpakuto in direct contact with the frost dragon rapidly became coated in a thick layer of ice. The ice spread to Aizen's sword-wielding hands and then began extending towards his entire body, attempting to freeze him completely.
Seeing this, Aizen unleashed his vast internal Reiatsu once more.
Boom!
Crack! Crack! Crack!
Both the ice covering Aizen's body and Toshiro's nearly spent frost dragon were utterly shattered by his immense Reiatsu.
However, before Aizen could catch his breath, Toshiro's voice rang out again.
"Vacuum Ice Blades!"
As Toshiro's words faded, the countless raindrops falling from the sky seemed to freeze in place for an instant. Then, under the influence of Toshiro's power, they instantly transformed into sharp ice blades, raining down on Aizen like a storm of pear blossoms… overwhelming, dense, and countless.