With Taienra's and the cats' help, Toz showed steady progress in learning the Dissolution spell, even if he was still limited to dissolving items.
Toz continued practicing his magic without a care, wanting to attain enough proficiency with Dissolution to use it in actual combat. Even if the spell itself didn't add much to Toz's fighting capabilities, simply learning the spell increased Toz's understanding of void magic, which, in turn, would improve the might and efficacy of his combination magic.
It seemed like Toz's practice with void magic and training with void mana together brought Toz to the brink of a breakthrough. Since he spent the free time he got after the battle with Dristel training his void mana, Toz was already nearing the boundary between the fifth and the sixth level with his void attribute. He wasn't surprised that his practice with void magic ended up pushing him to the brink of breaking through to the next level.
Toz wasn't sure what to feel about how learning a spell had progressed his mana, but he didn't mind. He didn't want to needlessly hold off on breaking through when he was already falling behind the cats, despite being the focal point of the talent sharing his inclination did.
Delaying the breakthrough might allow a mage to hone their magic and mana control further to increase the success and effect of their breakthrough, which would make them stronger and let them progress further without hitting a wall.
However, Toz felt like he had already reached the limit of what he could achieve in regard to the quality of his mana while still at the fifth level. And his mana control was already at a level where he wouldn't progress without breaking through to the next level.
With the approaching breakthrough, Toz took a break from practicing the spell and calmed and restored his mind. Reading a grimoire and learning a spell sapped a lot of mental strength. And if Toz's brain was too tired, his breakthrough might not be as successful as he would like.
Like his previous breakthroughs, Toz planned to push his mana and mana pool to the absolute limit while condensing his mana as densely as possible. If he was too tired, he might be unable to sense how far he could push his mana pool and might either complete the breakthrough too soon, leaving him with untapped potential. Or if he's unlucky, Toz, while not sensing the state of his mana pool, will push it too far and overexert or damage it.
A simple sprained mana pool will recover in time as long as Toz doesn't use too much magic. But depending on the damage, Toz might never recover. In a best-case scenario, a damaged mana pool won't cripple him, but it will still freeze Toz's path forward, and he will stay at the sixth level until he dies or encounters a miracle.
However, the spell wasn't complex enough to force Toz to drain his brain completely, and he was ready to go after only a little rest.
Since it was his first breakthrough to the sixth level, it was very likely Toz wouldn't be able to control his mana perfectly during it, so he warned Taienra and the cats just in case.
The cats, especially Lucy and Mindle, took his words of caution a little more seriously than Toz intended and became his self-designated guards as he began his breakthrough.
Since it was a breakthrough within the same division, the procedure wasn't needlessly complex.
Toz began by mentally grasping the void mana in his mana pool. In order to achieve as much efficiency as possible, Toz performed the three main parts of breaking through simultaneously.
He condensed the lump of void mana, converted the other elements in his mana pool into void to fuel and expand the chunk of void mana, and converted and absorbed the surrounding mana to expand the gathering of void mana even further.
To increase the size of his mana pool, Toz had to continuously pressure it by squeezing more and more mana into it.
The pressure from the mana forced the mana pool to expand, and the mana pool's resistance helped Toz condense his mana into an increasingly thick, dull grey liquid.
As Toz progressed in his breakthrough, the shell of his mana pool expanded, but it grew thinner and thinner in exchange. Toz didn't stop, and he continued to push mana into his mana pool. However, he slowed down so he could make sure that his mana condensed and became as thick as it could be.
Eventually, when he felt like his mana pool wouldn't be able to handle any further expansion, Toz stopped absorbing more mana and focused on getting the ball of void mana under control. Toz managed to condense the ball just a little more, which allowed him to push in another drop or two of the mana he absorbed.
Since he was breaking through to the sixth level, he converted the mana in his surroundings into mana of suitable quality and attribute.
Toz finished the breakthrough as beads of sweat appeared on his forehead due to the concentration required to control and keep his mana in check. Until he completed, the mana might break free from his control and shatter the mana pool on its way out.
But as soon as Toz was satisfied, the mana accepted it and calmed down. His mana pool began hardening and regaining the strength it expended to accommodate Toz's breakthrough.
However, the overflowing mana still affected Toz's surroundings as a wave of void mana spread out around Toz when he finished.
Thanks to Toz's practice with the Dissolution spell, the void mana used Toz's experience with void magic and carefully began to dissolve Toz's surroundings.
Thankfully, it wasn't strong enough to do more than peel off a layer or two of the tree's bark, and the wave dissipated before it could even reach the two cats who stood on guard a few meters away.