The next day.
Today, Toshiro didn't attend classes. He had specifically requested leave from the academy.
After leaving the academy, Toshiro used Shunpo to travel a great distance, arriving at a mountain far from the Seireitei.
Toshiro carefully surveyed the area. The mountain was remote and desolate, with no people around.
Satisfied, Toshiro nodded. This place suited his intentions perfectly.
The reason for taking leave and finding this secluded, uninhabited place was simply for Toshiro to unleash his power fully and gauge his actual strength.
Although he could also enter his Inner World where his Zanpakuto resided and use his abilities freely, Toshiro's Inner World was an endless expanse of icy plains, with ice everywhere.
Even if he used his abilities, he'd only be freezing ice, making it hard to assess the environmental impact.
Shing!
Standing atop the mountain peak, Toshiro drew Hyorinmaru and held it in his hand.
Then he whispered softly, "Sit Upon the Frozen Heavens, Hyorinmaru."
Boom!
Several pillars of icy blue light erupted skyward, and dark clouds gathered above.
Boundless, bone-chilling cold air condensed into a frost dragon dozens of meters long. Holding Hyorinmaru, Toshiro lightly swung it toward a distant mountain peak. The frost dragon instantly charged at that mountain.
Crack, crack-
Even before the frost dragon touched the mountain, the frigid air dispersing from its body had already frozen the entire peak.
Boom!
The frost dragon collided violently with the mountain.
Crack!
The entire mountain shattered, transforming into countless tiny ice crystals that scattered.
"Icicle Birds!" Toshiro murmured.
Whoosh, whoosh, whoosh!
Countless ice pellets flew like flocks of birds toward distant trees.
Instantly, continuous cracking sounds of freezing echoed. The forest turned into an icy plain.
"Ice Dragon Tail!" Toshiro unleashed a massive slash forward. The path swept by his blade tip instantly froze.
"Vacuum Ice Blade..."
Next, Toshiro employed various abilities available after Hyorinmaru's Shikai. After comparison, the frost dragon's power remained the greatest.
Toshiro stood still, deep in thought.
In the original work, Hyorinmaru had numerous techniques, probably the most among the Gotei 13 Captains' Zanpakuto, and the moves looked spectacularly gorgeous.
But they were only flashy in appearance. They never seemed effective against enemies, always easily countered.
Although Hyorinmaru's current name and techniques appeared the same as before, judging from the effects just now, the power was incomparable to the original.
Moreover, Hyorinmaru's attacks now had greater impact and wider area of effect.
Facing large groups of enemies, Toshiro would undoubtedly become their nightmare.
'But there's still a lack of a finishing move, a trump card to decide battles. Should I develop a new technique?' Toshiro thought.
A Zanpakuto's abilities aren't fixed. As a Shinigami continuously develops and refines them, the Zanpakuto's abilities also optimize, becoming more powerful.
"So, what technique should I develop?" Toshiro pondered.
Various Shinigami'a abilities flashed through Toshiro's mind.
'Ichigo's Getsuga Tensho is quite good… simple, practical, cost-effective.' Toshiro suddenly thought.
Ichigo used Getsuga Tensho from beginning to end, never changing even by the finale, indicating this move had its merits.
Getsuga Tensho's principle was also simple: condense high-density Reiatsu through the Zanpakuto, then release it.
However, although condensing and compressing Reiatsu to increase its density sounds simple, that was an inherent ability of Ichigo's Zanpakuto, Zangetsu, not something anyone could use.
'Can I do it?'
Thinking this, Toshiro instinctively mobilized his own Reiatsu, continuously gathering and compressing it into his Zanpakuto.
As more and more Reiatsu gathered on Hyorinmaru, its density increasing, the blue light on Hyorinmaru grew brighter and brighter.
When compression reached its limit, Toshiro swung at a distant hill. A blue slash flashed by.
Boom!
After a tremendous sound, the distant hill was sheared flat. The severed section instantly froze, then with a 'crack', shattered into countless ice fragments.
'Wow... such immense power.' Even Toshiro himself was shocked.
Of course, this was because he had compressed for a long time, achieving extremely high Reiatsu density, resulting in such power.
In actual combat, enemies wouldn't give him such preparation time.
However, even after brief compression, Reiatsu could gain significant power. Moreover, with continuous practice to reduce compression time, he could eventually achieve that level of power.
'But isn't this Zangetsu's ability? Why can I do it so easily?' Toshiro was somewhat puzzled.
Although he wanted to draw inspiration from Getsuga Tensho, he hadn't expected to achieve it so easily.
'Wait, that move seemed to consume a lot of mental energy earlier. Could it be...'
Reiatsu is guided and controlled by mental energy. Forcibly using mental energy to compress Reiatsu into high density is possible, but the consumption is too great, the gain not worth the loss.
But Toshiro, due to transmigration, possessed mental energy far surpassing other Shinigami. This consumption wasn't a big deal for him.
Hence, he could accomplish it easily.
'Hmm, such a powerful technique deserves a cool name. But what should I call it?' Toshiro had slight naming difficulties.
'Getsuga Hyorin? No, no, that sounds obviously plagiarized.'
'How about [Ice Dragon Flash]?' Toshiro thought of the blue flash released by that move.
'Mmm, not bad. Seems my naming talent is as impressive as my training talent.' Toshiro nodded confidently, believing the name he chose was excellent.
However, if he could compress Reiatsu into high density and release it, could he also compress the Reiatsu within his own body?
That way, even if his Reiatsu quantity didn't increase, but its density multiplied several times, wouldn't that mean his strength could also multiply?