Aaron could have improved much but there is a limit that the body can bear. Improving stats by 10-15 is already his limit for now. He may be awakened but he is still a mortal at level 15.
Even though he would gain 10x attributes for every level up due to his talent, he can't use them immediately. If he does that, he will lose control over his body. So, he made sure to improve to the limit that didn't cause him discomfort.
Among his skills, he improved Summon Undead skill to Rank 7 and Death's Disguise to Rank 6.
The reason for upgrading Summon Undead is pretty straightforward. The more skeletons he had, the better protection he would have from enemies. Moreover, they are the main attacking force.
He has no direct attacking power, which is a hidden danger for him.
If by chance an enemy bypasses his skeleton shield, then he would die as he doesn't have any truly attacking skills nor proper defending skills.
Aaron is not stupid to not know this but to get a skill is not an easy thing. The school gave a skill as a gift for awakening. Otherwise, there was no way he could have been able to afford to have [Sprint] in his status.
He knows that he needs to find a proper defending skill and also an attacking skill, but the present him can't afford such a cost. So, he has to make do with the skeleton shield.
He has improved the rank of that skill from Rank-5 to Rank-7.
The same thing that happened when the skill rank reached 4, happened when it reached 7.
Till Rank-3, the increase in number of skeletons was only 5, but from Rank-4, the increase was 10 for every Rank up in skill.
When Aaron upgraded it to Rank-7, the increase was 20 skeletons.
Now at Rank-7, Aaron could summon 20 skeletons at a time. It increased the number of skeletons he can have to 70. They are a lot of skeletons and he can use them to easily wear down the enemies.
By estimation, when he ranks up this skill to Rank-9, he would get 110 skeletons. More than a hundred skeletons, that's a small army. With this, it won't be easy to defeat him.
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The other skill he improved was Death's Disguise.
This is the new description of the skill after the improvement.
[Death's Disguise (Rank 6): Become synonymous with death. No life detection skills would be able to track you while the skill is active. You can now use the skill on a group of up to four people, including yourself.
Mana Cost: N*25 mana/minute (N-number of people)]
At Rank-0, it would cost 50 mana per minute. When Aaron increased it to Rank-1, the mana cost decreased to 45 mana per minute. It means he could save 5 mana per minute when compared to before.
It continued till Rank, where the cost was reduced to 35 mana per minute.
When Aaron increased the skill rank to Rank-4, the mana cost kind of remained the same but a development happened.
Before he could only use it on himself but now, he can cast that on others but he can only cast the on up to two people, including himself. It means he can only cast on a single outsider.
When he ranked the skill to Rank-5, there was a reduction of 5 mana in cost and also an increase in the maximum number that he could cast the skill on. It increased to three, including him. He can now use the group if there are only two more teammates.
Finally, at Rank-6, there was again a reduction of 5 mana in cost and also another number on whom he can cast the skill now, making it a total of four, which means three outsiders.
Of course, this plus has also its minus.
If he uses only on himself, the cost would be 25 mana per minute but if he adds one more, it would be 50 mana per minute and it rises to 75 mana per minute if another was added.
For every person added, there would be an increase of 25 mana per minute cost, which is not a good thing to use for a long time but skills like these would be useful in some dangerous situations.
If he ever worked in a team, and if they were in danger, he could use this skill to help them from the enemy trackers but that was not something he didn't see happening anytime soon.
Death professionals usually go out solo. They have skeletons, so they won't usually team up with others.
Also, many look down on death professionals. So, they don't like to team up with such pricks as that would mean they were only demeaning themselves.
Anyway, Aaron wanted to continue ranking up but that wasn't possible as ranking up a skill to Rank-7 would cost 100 SP, which he lacks now. So, he stopped there.
There are more than enough to rank up [Death Lash] and [Sprint] but Aaron didn't want to waste those SPs.
These skills, he used a lot but just by using them ranking up to Rank-4 is not so simple. If not for the improvement he would get due to talent, he would have used SP to improve them but he could feel that they were on the verge of reach Rank-4.
He assumed as long as he used them for a few days while levelling up, they both could reach Rank-4 before he had to leave for the academy.
Death Lash is not a problem but Sprint is.
When he started out, every monster that was present in the dungeons was like a death sentence to him but now, they are very weak and can't harm him.
Back then, he used Sprint every once in a while to survive but with the reduction in danger, he doesn't need to use as much as did in the coming days.
It would be useful again when he enters higher-ranking dungeons in the academy but now, the chances of increasing the rank of [Sprint] are very low but he wanted to give it a try.
SP, even though he gets a lot of them is still precious.