Over the next few days Nero's stats continued to rise at a good pace, the majority of the increase being thanks to the training he was recieving from Rias
His days consisted of making breakfast for Aurathia and Yumi, after which he would spar with Aurathia with her updating his status after they were finished, sometimes Yumi would spar with him afterwards if she thought that his footwork was slipping and that he needed to be reminded what to do
After that he and Yumi would head into the dungeon, casually chatting as they made their way down the floors, the two of them seperating at floor 6 where Yumi was confident in taking care of herself with Nero making his way further down
Thanks to the training with Rias, Nero's control over the power of destruction was much better and due to the increase in his stats he was now able to take out a hard armored in a single shot, and was even able to take out an infant dragon, albiet with some difficulty, leading him to having the confidence to head down to the 12th floor and then the 13th due to floor 12 having the same monsters as floor 11
Due to the amount of different types of new monsters that there were on the 13th floor Nero decided that it would be his hunting ground for the time being until he was confident that he was used to the different monsters movements, basing his skill level on the training that Yumi gave him by trying to put himself in a one on one situation and then dodging the monsters attacks for 1 minute
"This floor is actually much better for getting me back into focusing on Yumi's skills" Nero thought as he dodged a Almiraj that was charging at him, the monsters movements one of the faster ones on the floor and it was able to use a small axe as well as its horn to try to attack Nero
"Also due to the small size of the monsters on this floor it is much harder to use the power of destruction to take them out without destroying the magic stone in the process" finishing the 1 minute of dodging he had been aiming for and taking the small creature out in a single strike to the back of its neck
Taking out the monster Nero heard a sound like a bell, looking up from gathering the magic stone he noticed that the energy that he needed to gather in order to summon his next trainer had been filled, the process having taken a much shorter period of time due to him being able to gather the energy needed more efficiently, thanks to the monsters in the deeper floors giving him more energy and his skills being much higher and more varied due to having finished his training with Yumi and starting his training with Rias
"I wonder who my next summon will be" Nero thought to himself, picking the magic stone off of the floor and chucking it into the storage space that he had finally managed to create due to his magic control and knowledge finally being enough for him to do so, something that made him even more efficient due to him not having to take the weight of his bag into account when dodging, as such he had given his bag to Yumi so that she could gather the magic stones of the monsters that she had defeated
As he was thinking a crystal mantis appeared from around a nearby corner, it spotting Nero and crying out before charging towards him
"A crystal mantic huh" Nero commented "looks like I'm trying power of destruction weapon enhancement again today"
Having come across a crystal mantis in the past few days, Nero quickly realised that like the infant dragon it had magic resistance, but its magic resistance was much higher, but he also realized that in the mantis's case that it was able to reflect magic back at him, something that caused a very close call the first time that he had faced one when he used the power of destruction against it and nearly ended up losing an arm due to almost being hit by his own attack, thankfully he was able to dodge it in the nick of time and the attack had dealt alot of damage to the mantis with a layer of its crystals having been shaved off an it's defenses being lower because of it, making it so that Nero was able to deal with it
Due to his tessen not being strong enough to break through the crystal armor, and him not wanting to accidently take himself out with his own power of destruction Nero came up with the idea that if long range attacks with magic were off the table, he would just have to use close range magic that couldn't be reflected back at him
Taking great care Nero coated Shirayuki and Hyōka with a thin layer of power of destruction, the mantis bringing its scyths down on Nero, bringing Hyōka up to defend
Stab
The mantis's scyth spun off and stabbed into the wall, the power of destruction cutting straight through the limb, seperating it from the monster
Having been trained to not ignore openings, Nero immediately used Shirayuki to decapitate the monster in a single movement, the head htting the floor before the body burst into dust
"It always makes me nervous doing that" Nero breathed a sigh of relief, having gone through multiple sets of weapons in the training zone before he was confident enough to try it out with Shirayuki and Hyōka in the real world
"I think that's a good place to leave it for today" Nero decided, always feeling quite drained due to how tense he felt after using the power of destruction weapon enhancement, picking up his latest spoils and making his way back up to meet Yumi to head back home.