Flaw

Immortals do not need any mortals to travel into an illusion world. In fact, mortals are just a burden; they can be of no help to immortals if the two move into the illusion world together.

However, Clocks Academy still took many mortals there to train their future generation; they treated their mortals well.

Still, taking mortals directly to the illusion world was dangerous; immortals couldn't perfectly protect themselves, so they had no power to protect the mortals there.

The risk of illusion worlds differs from one world to another, but the rule of thumb is that the power of visiting people doesn't really matter. Immortals are just as much in danger as mortals in an illusion world, or at most, they are only at a bit less risk.

Even immortals may die in the illusion world, so there is no spare energy to care for mortals. That is unless the immortal is rank 12 and can crush the entire world alone.

The researchers were aware of the risks and that immortals couldn't protect them, so all those willing to visit there were the ones entirely dedicated to their path, almost fanatics of the illusion concept.

…

Soon, the newly formed illusion world corporation set up zones that could be visited by mortals.

The Mount sect also sent some mortals, but the mortals they sent were all relatives of the sect's elders. There were far fewer mortal illusion researchers from the Mount sect.

This shows that mages were much more meritocratic, while cultivators were more tribal. Still, even though mages were much better at researching things and had far larger libraries, the firepower of cultivators was evidently stronger, as the old patriarch of the sect had over a million complete laws.

For cultivators, they usually refer to rank 10 immortals as true immortals and refer to rank 11s as law immortals. The names differ in different cultivator sects and worlds, so there is no general rule.

With the initial setting done, both sides sent their first batch of mortals. Mortals who were sent were truly privileged; if they managed to gain mastery of illusion, their future path would be guaranteed.

But it was undeniable that they were sort of guinea pigs as the immortal cultivators waited for the first batch of mortals to return from their trip before they went in.

…

Miles looked down.

An immortal mage gave him a rank 9 airship and patted his shoulder before leaving.

For a rank 3 mage to be given a rank 9 airship would be unbelievable in normal circumstances, but in the current situation, it wasn't strange.

Each person sent was talented in the illusion path, so the academy wanted to increase their survival rate; rank 9 airships are expensive, but talents are more expensive. It would have been a waste if they gave a lower-ranking airship, and the talented mortals died before reaching the world.

Normally, not even rank 9 airships could move through the endless space because of the existence of chaos energy. But, for this batch of mortals to reach the illusion world successfully, the immortals cleared a narrow path from any chaos energy.

The alternative was giving the mortal researchers each a rank 10 airship, which would have been astronomically expensive and may not even have been possible.

Every mortal researcher was given their own exclusive airship; otherwise, if they just packed everyone into one airship, everyone would die if something went wrong with that ship.

Another choice was to pack everyone into a rank 11 airship, but this was also no good, as while a rank 11 airship can protect against chaos, it cannot protect them when it enters the illusion world. Then, if something goes wrong in the illusion world, everyone will die.

To increase the chance of gaining something, the best solution was to give everyone their own rank 9 airships and send them, hoping some get lucky and achieve something.

Everyone also left behind a soul lamp back in the academy, so their lives and deaths would be known to the academy if the illusion didn't intervene with it.

The immortal mages also gave a few protective items to everyone, but they may not be that effective.

...

Looking around from the windows, Miles sighed; the endless space, while dark, was beautiful.

He could see the faraway light of other worlds; one might look and mistake it for the night sky, but Miles knew of the existence of other worlds, so he knew that every light is another entire world.

"So majestic!" Miles sighed.

Looking ahead, he saw a world shining with different colors; its shape was not visible; one moment, it was a circle; the other, it was a cube.

Before boarding the airship, the immortals taught him about operating it and specially made simplified commands and interfaces to ease his and other mortal researchers' work in handling it. Looking at the airship's shields, Miles nodded; if there was any chaos, the shield would have burned through and been destroyed.

He is already very close to the world, so the least dangerous part has nearly finished.

The 'only' part left is exploring the illusion. Miles brought some equipment for this, but those can only be used for observation and cannot solve any danger. He only has to hope he lands in a safe part.

The immortals have already conducted a preliminary observation and have confirmed the illusion has possibilities suitable for mortals. It is not like they would die the moment they land.

But, being suitable to step foot in them doesn't mean mortals are safe remaining there. He may still die and never be able to return.

"But I don't care!" Miles steeled himself.

"Here we go!" he opened his eyes wide, not intending to miss anything as the airship entered the illusion.

…

Illusions are dreams of the universe. There may be ancient secrets in an illusion that no mortal or immortal knows.

One may obtain ancient knowledge about things nobody knows about. One may also be able to gain mastery of the concept of illusions.

Looking around, Miles frowned. He was in the airship a moment ago but suddenly appeared in the middle of a lush forest.

He looked for signs. Illusions are very close to reality, but there are always some signs that display they are not real. One must find the sign as quickly as possible; otherwise, one will turn into an illusion.

Looking around, he found trees, no animals, and even an ant. But, the lack of animals by itself was not a sign; there could be forests in the real world that don't have any animals.

Looking at the sky, he found it weird that it was black, with some patches of green in some places, but it was still not a sign; there are many places where the sky might be like this; those green patches might be green clouds.

He looked down; the soil was black, which was not the norm but not a sign.

"Fly!" he cast a spell and flew into the sky.

He nodded; it's good that his magic works; it did feel weird, though.

It was as if controls were reversed; the magic took him down when he thought of moving up.

A second later, he felt his magic power increasing in expenditure; he could only move up 4 meters from the ground. If he tried to move any higher, his expenditure would skyrocket many times; maybe immortals could afford it, but he certainly could not.

Looking from 4 meters, he saw trees but couldn't see the outline of the forest. To begin with, many trees were far longer than 4 meters, so his vision was still obstructed, even though he was 4 meters high.

Moving around, he found a tall tree, carefully sat on it, and looked around; he could not fly high using magic, so he could only climb trees.

"Body strength boost!" he cast his spell.

The magic worked, but it began burning through his reserves quickly.

"It's not just the fly spell! Any magic would cost a lot when high above!" He sighed.

This means he could only climb the trees with his physical strength without using magic. Still, it was okay; mages have weak bodies, but that is compared to other professions like knights. Compared with mortals, mages have superhuman physical bodies. 

After climbing one meter, Miles wiped the sweat on his forehead. "This is not normal!"

He felt so tired as if he had run hundreds of kilometers while climbing this one meter.

"It was not only magical expenditure that increased; physical climbing also is so tiring." he thought.

Looking down, Miles began to sweat coldly; he couldn't see the black soil. Instead, water was everywhere, and it was getting higher.

"Where is all of this water coming from?" he thought. It seems that he would be drowned if he fails to climb, but with it being so difficult to climb, could he climb enough? How far can the water reach?

Again, water in a forest is not a sign; it's not beyond the realm of possibilities in the real world.

Looking down, he carefully calculated; the water was moving up one centimeter every one minute. He is now 5 meters high, meaning he has at most 500 minutes.

He doesn't know exactly how far the water reached by now but estimates it to be 30 centimeters.

So, he has 470 minutes left to think of a way.

"Scary!" he thought. Logically speaking, mages could survive underwater quite easily, but that is normal water; who knows what this illusion of water is? And, even if it is just normal water, when does it stop? If the water keeps going up by 1 centimeter forever, eventually, the pressure will be enough to crush even a rank 3 mage like him.

Closing his eyes, he began thinking about all the details so far.

"Water in the jungle … there should be a source for it!" he opened his eyes and started climbing down. At the moment, climbing up is too exhausting and quite useless.

Now, he must find the source of the water, and finding it is easier when lower in altitude.

Illusions follow natural laws nearly completely and only have small but crucial flaws. So, if there is water, there must be a source; if there is water with no source, that would be a flaw.

The problem is that guessing doesn't work; he must be sure there is no source. Finding the source in this massive forest will take time and may not even be possible, but now, he has only this clue.

Activating accelerating magic, he moved at an altitude of 3 meters to reduce expenditure. Fortunately, at 3 meters, expenditure was normal.

Thinking of something, he stopped and dropped a piece of wood in the water. It dropped in and started floating on it.

There was no wind, water current, or rain; the water was not pure, and the soil below was not visible.

"The water surely looks like normal water!" he thought but didn't dare to touch it.

From up above, he cast "water control" magic.

Even though he is an illusion mage, he can cast these spells.

The spell hit the water below but didn't have any effect.

Shaking his head, he cast another spell, "Illusion dissect!".

Illusion dissect was a specialized spell of illusion mages; it was able to pierce through illusions.

Hitting the water, the spell caused a ripple but could not break through.

"The water is an illusion!" The look on Miles's face became very gloomy. There would be a physical water source, like a river or a sea, if it was normal water.

But, with it being illusion water, there may not be any physical source. Therefore, finding the source of the water is nearly impossible.

"But, why is the water muddy?" he thought with doubt. If it is an illusion water, it should not be muddy like this. Illusion water is never muddy unless it is contaminated by something.

"It is contaminated by the soil? Or…" Miles looked up.

"There is something wrong with this sky!" he felt it; the color of the sky changed from black to muddy black, with green patches.

"Illusion dissection!" he cast. The spell flew!

As expected, it didn't hit anywhere, and there was no ripple, but Miles discovered something from the response to the feedback of the spell.

"The sky is a reflection! It reflects this forest! The sky is not the sky!" he thought with fear.

"The sky is ... an ocean! It reflects this forest! It was black before because it reflected black soil; it is muddy now because it reflects the muddy water. The green patches are trees!" he thought of the weird feeling of the Sky spell, where it worked in reverse.

In fact, it was not working in reverse; it was working fine.

"I am sure! This is the flaw!" as he thought of this, everything suddenly turned upside down!