Although Leon couldn't use Instant Mastery since he didn't have nearly enough mana, he managed to level it up to the level two hundred the few times he used it. It wasn't that unexpected given how much mana he used, and in fact, he thought he would level the skill up many more times.
Instant Mastery
Cost: 60.000.000.000 mana
"The cost still will be stupidly high at the level max, but at the very least, it will decrease by three times," Leon nodded after checking the cost of the skill. "Regardless, I can't stop my training now even if Ilyana isn't around."
Fortunately, the next time Leon obtained a portion of Netro's memories, he finally found some clues as to how to use conceptual attacks. It wasn't a skill, so Leon wouldn't be able to automatize the whole process. However, that also meant that Leon wouldn't have a bunch of restrictions.
"It looks like the system doesn't recognize conceptual attacks…" Leon frowned. "I wonder why…"