Twenty-five seconds to go!
Neltharion had captured the pictures of the restricted military zone from various angles, including the fixed routes of the two patrol teams, and transmitted the data back to Li Yao's brain for modelling.
Li Yao's biggest concern was what to do if the patrol team suddenly changed their route half way.
Jin Xinyue had mentioned that, according to the standard military tutorial of the coalition army of demons, every patrol team would have three to four different routes, and they would choose a random one every half hour or so.
If Li Yao and the Fire Ant King had more time to observe, they would probably have been able to see through the pattern.
However, they only had several minutes to prepare. They could only try their luck.
In case the patrol teams really changed their routes, Li Yao had to prepare backup plans.
Based on the terrain inside the prohibited military zone, Li Yao calculated twenty-three new routes that the patrol team could possibly chose in advance and made sure that it would take him seven seconds at best to pass through them.
Fifteen seconds to go!
The Fire Ant King took out a delicate cylinder from his pocket and turned it open. From the cylinder flew out two black beetles with a green, vertical stripe on their back.
Under the Fire Ant King's manipulation, the two beetles flew higher and higher. They passed the high wall out of the prohibited military zone and reached the entrance of the No. 2 ventilation tube.
Five seconds to go!
Li Yao took off the clothes of the treasure merchant and put on a new membrane suit.
The new suit was truly as thin as any clothes could ever be. It stuck to his body like a second skin without leaving the tiniest gap, highlighting the trace of his every muscle.
Shua!
Li Yao touched a rune on the waist of the suit. Ripples spread out on the surface of the bright gray suit as it gradually turned translucent. In the end it had almost completely blended into the air. He was now invisible!
It was a cellular invisibility cloak that the specialists of the Blade of Chaos had created by retrieving the cells of multiple kinds of demon beasts that boasted discoloration and mimesis abilities, such as chameleon.
When the wearer was absolutely still, they would be hardly able to be discovered, like an ice block that was tossed into water.
The only drawback was that the constituents of the cellular invisibility cloak were all highly active. They had to be preserved in special culture solution. If they were brought out and exposed to the air, their longevity was no more than five minutes.
Generally speaking, the invisibility cloak would gradually lose effectiveness after four minutes and a half.
Furthermore, the invisibility cloak worked best when it was still. If the wearer was moving at a high speed, they would still leave blurred shadows behind them, making the air unusually twisted.
Zero seconds to go!
Li Yao flew out like a stream of smoke.
Shua!
He keenly sensed the net of high-heat rays on the high wall of the prohibited military zone. However, he simply constricted his bones and muscles to the minimum before he crawled through the gaps of the net in a size no larger than a cat!
Two patrol teams were moving away from the No. 2 ventilation tube. Li Yao calculated the estimated time of their return while he observed the angle of a few biochemical surveillance eyes on the high wall. He moved fast between the blind angles no larger than the tip of a needle and approached the target quickly.
Right then—
One of the patrol teams returned earlier than expected before they reached to the end of the prohibited military zone, switching to a new route!
Damn it!
They had a second patrol plan!
Li Yao stopped his movements instantly. His heartbeat and breathing were suppressed to the minimum. Even his pores were entirely locked, not giving out the slightest heat or scent. He watched the patrol team walking right toward him while doing nothing.
As long as he remained perfectly still, the invisibility cloak would function perfectly for five minutes, which should be enough for him!
The patrol team brushed past Li Yao. The soldier closest to him would have touched Li Yao's head if he had stretched out his arms.
Thankfully, they did not notice that the air so close to them was slightly warped compared to usual.
Li Yao remained still for another half a minute. With the help of Neltharion, he observed their new patrol route.
After switching to the second patrol route, the blind angles of the two patrol teams were completely different. Everything had to be recalculated.
After calculating for one minute and two seconds, Li Yao took action again!
Deep inside his brain, the biochemical eyes over his head and the eyes of the soldiers of the two patrol teams seemed to be shooting out crimson rays and formed interconnected lines of death in front of his face.
The death rays were changing all the time, and he danced forward. While sometimes moving quickly, sometimes slowly, it took him more than three minutes before he struggled his way to the entrance of the No. 2 ventilation tube.
In order to send air into the main body of the enormous Eye of Blood Demon, every ventilation tube was more than half a meter in diameter, which was spacious enough for a middle-sized adult to crawl in.
However, the entrance of the ventilation tube was covered in an extremely dense iron gauze, surrounded by anti-cutting alert rune arrays.
Li Yao glanced quickly and recognized the mechanism of the alert rune arrays. They would send out warnings when they perceived vibrations.
Once the iron gauze was broken by brute force, there would certainly be unusual vibrations. Alarms would ring the moment such vibrations were detected.
Shua! Shua! Shua! Shua!
Inside the iron gauze, half a meter into the tube, three enormous fins were spinning at 1,500 rpm. Aggressive rune arrays of the wind class had been carved on the fins, too, raising unstoppable stormy blades that turned the part of the tube into an invisible mincer.
There were forty-five seconds to go before the invisibility cloak completely lost its effect.
Zi. Zi. Zi. Zi!
Li Yao sensed that the invisibility cloak was turning stiff.
It was a sign that the stealth cells were about to wither.
At this moment, the two patrol teams had reached the point where they were furthest from him, and all the biochemical eyes happened to be scanning other areas.
However, after the change of routes, the time left for Li Yao was only eleven seconds!
Good enough!
Li Yao's hands turned into two clusters of gray mist instantly. He stuck four pieces of magical equipment that looked like magnets to the alert rune arrays softly at first, establishing a temporary circuit that guided the alert rune arrays into a wrong path. As a result, they would neglect the minor vibrations on the iron gauze.
Then, Li Yao rubbed off a huge amount of rust from the iron gauze with a sharp dagger and carefully stored the rust.
It only took Li Yao three seconds to finish the preparations.
Then, he drew a circle on the iron gauze and cut it open, crawling into the ventilation tube!
It was not difficult to break the iron gauze. What was really tricky was how to restore it!
The two patrol teams far away were already turning around, and the two biochemical eyes were slowly shifting to the entrance of the No. 2 ventilation tube, too.
Li Yao's ten fingers were like boneless snakes, with a tiny needle between every two of them.
The needles were in fact hollow, with a tiny sac behind them in which a tiny amount of natural glue was stored. They were originally tools to fix the components of super-mini magical equipment.
Manipulating the tiny muscles on his fingers, Li Yao squeezed out the glue through the needles and stitched the iron gauze again. He intentionally left some additional glue at the edge of the fracture before he blew the rust that he had rubbed off earlier back.
Eventually, he took out an aerosol can and sprayed on the iron gauze.
The next second, a thin layer of dust appeared on the 'rusty' iron gauzed. There were even broken threads that seemed to be remnants of a spider web.
At first glance, it was utterly immaculate. There was no trace that the iron gauze had been broken through at all.
It was not until then that Li Yao attracted the four 'magnets' through the gaps of the iron gauze with his spiritual energy, restoring the alert rune arrays to their original state.
Shua!
The biochemical eye glanced past the entrance of the No. 2 ventilation tube, noticing nothing wrong.
But the invisibility cloak on Li Yao's body had reached its limits, too. Twisted spots of light were already appearing.
Had the patrol team been any closer, they would certainly discover the fuzzy, gray shadow behind the iron gauze.
The Fire Ant King's two black beetles, on the other hand, had crawled into the tube together with Li Yao and crashed toward the rapidly-revolving fan!
Because of the high speed and the strong attraction force, the fan often absorbed small bugs.
The two black beetles, on the other hand, were the 'Green Oil Fire Bugs' that the Fire Ant King had carefully refined. After they crashed into the fins, they exploded into two tiny fireballs!
The two fireballs jammed the rune arrays of the wind class on the fins. The fan's self-protection measures were activated. The speed of the fan was lowered as it prepared to discharge the foreign object.
Li Yao took the opportunity to observe every detail of the spinning fan while his eyes were bulging and his pupils were shivering. He also perceived the wind blades, which were invisible to human eyes.
Shua!
He successfully crawled through the fan in the gaps of the fins whose speed was 780 rpm!
Three wind blades cut into his body brutally. But he had tensed the muscles all over his body and did not shed a drop of blood.
Half a second later, the speed of the fan returned to 1,500 rpm, and the patrol team walked past the entrance of the No. 2 ventilation tube.
Attracted by the sound of the exploding bugs, they looked at the inside of the No. 2 ventilation tube through the iron gauze suspiciously.
The fan was running stably. Except for the quickly spinning fins, they saw absolutely nothing.
The vague smell of something being burnt, however, made them realize that a few bugs had just been sucked into the fan.
The rust, dust, and spider threads on the iron gauze all eased their suspicion, which was not too high in the first place. The patrol team returned to their normal route and left the insignificant incident behind.
Behind the fan, Li Yao wiped off the cold sweat on his forehead and grinned.
The infiltration from the fourth alert area to the third had half succeeded!
In front of him was a dark ventilation tube that led underground. All kinds of lethal bugs were the guardians of the sunless world!