Leon waited for several hours, but nothing happened. In case he received some unexpected visitors, Leon created a hole in the ceiling of the cave and hid it with the earth. Still, it wasn't a good idea to use that place to hide. If a mutant devourer appears at the same as the grizzly giants, his temporary hideout won't help him in any way.

"It looks like the grizzly giants don't intend to come... they probably already know about the usual time the mutant devourers appear, so I think I am safe for the time being."

Leon wondered if it wouldn't solve the problem, just kill all the devourers of the other world. However, in the end, he decided not to do that. First of all, if that were an excellent way to solve the problem, Ilyana would have told him that. The grizzly giants would notice that someone interfered with them if the monsters just suddenly disappear, so that wasn't a good idea.

Also, even though that would probably decrease the spawning rate of the monsters, it was a bit too much to hope for that Leon would find all the devourers of the other world. They were essentially massive earthworms, after all.

"Some distractions could help me, but the people of this world if something happens around this place and then soon after the problem of the mutant devourers is solved... I can't do that."

In the end, Leon decided to just wait for the monsters. He couldn't leave any signs of his presence lying around. Leon's only option was to deal with the monsters whenever they appear and when the inhabitants of that world aren't around. Besides, he was in a world that was in the second stage of assimilation. Time there passed ten times faster than in Ilyana's world, so if anything, that were a good chance for him since eventually he wouldn't be able to go to that kind of world anymore.

It has been a while, so Leon decided to meditate since Zen would make him unable to feel or hear the things that may happen near him. Much to his surprise, the skill leveled up ten times before the first mutant monsters finally appeared.

Congratulations! The skill Meditation has leveled up.

You obtained 01 status points.

Congratulations! The skill Meditation has leveled up.

You obtained 01 status points.

Congratulations! The skill Meditation has leveled up.

You obtained 01 status points.

...

Leon didn't know if it was because the concentration of mana inside that place was high or if it was because he was in a world that was on the second stage of assimilation, and that made everything more efficient, but he could think about such things later. Leon left his temporary hideout and immediately felt his mana being drained by the creature that just appeared in front of the purple crystal. Even without eyes, the grotesque monster could feel Leon's mana and pointed its arms toward him. However, whatever that thing was trying to do. It missed because Leon used Transfer and started to absorb its mana when it landed on the back of it. In just two seconds, Leon drained all the mana of the beast and then made it levitate using Telekinesis before using earth to cover the creature's whole body and then compressing everything inside of it. Leon tried to compress the earth sphere until it becomes of the size of a soccer ball, but he failed. The best he could do was to decrease the size until it was tall as himself.

"I guess this will do... I just have to hide this in the ceiling. As long as it is inside my earth sphere, it won't be absorbed by the land, after all."

To confirm that everything was going as planned, Leon counted the seconds until the next mutant devourer appeared. The creature appeared after exactly three hundred seconds, but that one Leon ignored it and let it move toward the exit of the dungeon. The grizzly giant would find that something was wrong if suddenly they stop coming, so it couldn't be helped. Leon had to create a tunnel on the ceiling of the dungeon in order to escape from the range of their Mana Tracking, but that was just a minor nuisance.

Three hundred seconds later, another one appeared, and this time Leon killed, and it also stored its remaining in a sphere of earth. Leon only noticed any difference after killing the tenth monster... the countdown decreased one second.

"Well, I guess this is progress... Did you guys notice the decrease of mana inside this place?"

"Yes," Celsius said.

"Yep!" Sylph said.

"You should take advantage of this place while you can," Undine said. "This kind of place rich in mana is rare to find. It will make your magic much more effective and increase the potential of your training by manifold."

"Is that so?" Leon rubbed his chin. "I killed a lot of Ilyana's monsters. Why the place we fought didn't become like this?"

"Because the monsters she created aren't the meat of flesh and bones," Undine explained. "Even if they were, you always drain their mana. Another important factor is the place... inside dungeons, mana can gather and concentrate with more ease. Someone as powerful as her can probably create a similar environment. I'm pretty sure her castle is similar to this place. Still, this kind of action can also speed up the assimilation process of the world."

Leon nodded since it made a lot of sense. Still, if he wanted, he couldn't train like usual in a place like that. Leon was in the middle of an important job, so the only thing he could do to take advantage of that was use Meditation... and so he did.