Castle of Black Iron

It would soon come to the vast vacant space out of the territory of Nine Heavens Big Domain if it kept going northwards from Redmountain City.

However, suppose the airboat’s speed was about 800 miles per hour. As the catastrophe facing Ying Clan’s castle had just happened over 6 hours, it means the airboat had just moved about 5,000 miles.

‘If that airboat keeps moving northwards, I could catch up with it.’

After reaching this conclusion, Zhang Tie instantly triggered his invisible shen beard as he set off the crown and shot like a lightning bolt towards the direction where the owl saw.

When Zhang Tie left there, he looked back as he found that an airboat with the symbol of Force Emperor Immortal Palace had just reached about 300 miles away from Redmountain City. Zhang Tie estimated that the powers assigned by Force Emperor Immortal Palace would soon arrive at Redmountain City.

Zhang Tie kept moving northwards in the air as fast as a lightning bolt. At the same time, he started to recall the look of the airboat according to what the owl had seen. After amplifying the scenes in his memory, Zhang Tie observed it carefully; because this airboat was the only clue for Zhang Tie at this moment.

The airboat that carried the immortal generals of Yin-Yang Sect was the commonest mini airboat in Motian Realm. Being only a bit longer than 100 m, it was the most classical air-feather class airboat in Motian Realm. It’s look and performance had already well adapted to the environment in Motian Realm. Its manufacturing drawing was open to the public in Motian Realm; therefore, it could be produced in many places. Perhaps the internal design of air-feather class airboat would vary according to different customer demands; however, they all looked same externally. Like vehicles with the same brand and the same type in Taixia Country, they almost looked the same externally. What was more, there was no emblem or flag of an immortal palace or a clan on the airboat. Such airboats could be seen everywhere across Motian Realm. There would be 1 air-feather class airboat in every 5 airboats in the sky.

Despite lotus-flower eyes, it was still impossible for Zhang Tie to look for such an average airboat from 5,000 miles away. If that airboat had just left Redmountain City for a couple of hours and was within 600 miles, Zhang Tie might be able to see it. However, the distance of 5,000 miles had already surpassed Zhang Tie’s maximal capability. Zhang Tie saw dense airboats within 1,300 miles in the air which were moving towards different directions. It was simply like fishing a needle from the sea for him.

However, it was also possible for him to fish a needle from the sea. What counted was that he should remember the look of the needle.

Even two leaves of the same tree were not absolutely same; so were airboats of the same brand and type. As long as the airboat had been used, it must have some distinctive features.

Fortunately, that owl had a pretty good sight. Although the air feather-class airboat was the commonest type, Zhang Tie still found three distinguishable features on it.

First, was it new or not? Given its look, that airboat was about 70% new. It was not painted yet. Given this feature alone, it could be distinguished from over 60% of air-feather class airboats.

Second, the trivial deviation between some points being exposed to the metal universal mortise and tenon structure on the hatch door of the airboat, which was caused in manufacturing and manual assembly. The trivial deviation existed between each two air-feather class airboats which couldn’t be noticed by commoners. However, after connecting the opposite corners of the hatch door with diagonal lines, the diagonal lines would become coordinates. In this way, the deviation would become an instinctive feature of the airboat.

Third, there were some trivial traces caused by light frictions on the left port side of the tail of the airboat which might be caused in the process of discharging cargo. There were always some light traces of friction near the discharging hatches on the tails of airboats.

These were the three features that Zhang Tie found in such a short period of time through the image in the memory of the owl. Although the owl had very good sight, it still couldn’t see all the details. If it were Zhang Tie, as long as he took a look at something, he could even find 300 features, not to mention 3 features. However, the 3 features were enough for him.

Zhang Tie couldn’t find the airboat with only 1 of the 3 features; however, after combining the 3 features, Zhang Tie would probably find it. Plus time and space factors, he was confident to find it.

Zhang Tie kept flying northwards while calculating rapidly in mind. At the same time, the map of the north region of Nine Heavens Big Domain appeared in his mind. Zhang Tie was making analysis quickly.

The airboat was flying northwards; however, it was just a general direction. Over the past hours, the airboat might have already adjusted its direction at any time. However, it would never turn around; otherwise, it would return to the territory of Nine Heavens Big Domin. Given the process of the raid last night, the leader of that action was definitely not an idiot. As long as he was not an idiot, he would never make such a stupid decision——turn around and move southwards after moving northwards for a few hours; because they could not make puzzles for their action by doing that; instead, they were just wasting time. Therefore, the earliest direction that the airboat moved towards after leaving Redmountain City last night must be their general direction.

However, it was Force Emperor Big Domain in the northwest of Redmountain City and Nine Heavens Big Domain.

Were they from Force Emperor Immortal Palace? Of course not. If the members of Force Emperor Immortal Palace discovered that the remains of Yin-Yang Sect were hiding in Redmountain City, they would definitely assign powers to get all of them aboveboard; instead of being such mysterious. Nor would they kill all the disciples of Yin-Yang Sect in the castle. At least they should catch them alive, the more the better, so as to display the magnificence of Force Emperor Immortal Palace. Additionally, what happened in Ying Clan’s castle was slapping Force Emperor Immortal Palace’s face no matter whether Force Emperor Immortal Palace could find that the remains of Yin-Yang Sect were hiding in Redmountain City or not.

Therefore, although those people were heading northwards, they would never go to Force Emperor Big Domain.

Therefore, at this moment, the airboat’s location should be within a sector region whose angle was 110 degrees. Within this region, the largest distance between Redmountain City and the airboat was 5,000 miles. The left line of this sector region at most neighbored the border Dragon Emperor Big Domain while the right line was at most horizontal to the east direction of Nine Heavens Big Domain; instead of pointing southwards…

As Zhang Tie thought about it, the map of Motian Realm in his mind had already become a holographic three-dimensional dynamic map. On the map, the sector region in the shape of a huge trumpet in the north of RedMountain City had already turned yellow. Meanwhile, hundreds of air routes covered this yellow region, which led to different destinations in various domains and regions across Motian Realm, the distance of which varied from thousands of miles to hundreds of thousands of miles. Now that the airboat had left Nine Heavens Big Domain, it should have a destination, which could only be one of the hundreds of targets in the sector region.

By multiplying the hours since the airboat had left Redmountain City by the maximal speed of the airboat and 70% of its maximal speed, Zhang Tie got a region. After covering the region on the hundreds of routes in the sector region, Zhang Tie got an eye-catching oval red air territory near the mouth of the trumpet of the yellow sector region. The entire red region covered over 5 million square miles.

Without emergency, Zhang Tie was sure the airboat was in the red air territory.

Additionally, the red air territory was expanding in each second. After a few more hours, the red air territory would become very vast which would contain much more unpredictable factors. However, at this moment, this red air territory was still within Zhang Tie’s tolerance.

So many airboats were lagged behind by Zhang Tie. At a high speed of about 30,000 m per second, it only took Zhang Tie a few minutes to travel 3,000-4,000 miles and reach the northern border of the red oval air territory in his mind. After that, Zhang Tie didn’t fly northward anymore; instead, he started to fly horizontally in a zigzag way.

Any air cavalry was clear that such a flight route was the basic tactical action for searching over a sector region. Similarly, if one wanted to search over a circular region, he needed to fly spirally, which was equal to plow the entire air territory generally.

Zhang Tie was the founder of the air force in Taixia Country. Even the books about air cavalries in Taixia Country were written by him. Of course, he could complete such a simple action easily.

On this occasion, only Zhang Tie could accomplish this task by searching over such a vast air territory within a short period of time at such a terrifying high speed and with his lotus-flower eyes.

As Zhang Tie crossed the red oval air territory at a high speed in a zigzag manner, he kept glancing over all the airboats within this air territory using his lotus-flower eyes.

Finally, after a few minutes, an air-feather class airboat over 300 miles away from him on his left was spotted.

At the sight of that airboat, Zhang Tie squinted his eyes at once. After confirming the 3 external features of the airboat, Zhang Tie sped up towards the airboat at once. When he was about 60 miles above it, Zhang Tie refreshed the airboat using his lotus-flower eyes. In a split second, the internal situation of the airboat became transparent to him. In the reinforced bilges at the bottom of the airboat, Zhang Tie finally saw the captives of Yin-Yang Sect.

All the captives of Yin-Yang Sect were in a coma. Being still, they were locked in two bilges according to their genders. After discerning them carefully, Zhang Tie saw Ji Yuelan and Jiang Ruoxin who were also in a coma. Until then the two women were still in men’s clothes.

After leaving Redmountain City for less than 15 minutes, Zhang Tie found Ji Yuelan and Jiang Ruoxin.

After confirming the two women were still alive, Zhang Tie finally became reassured. Meanwhile, it proved that his judgment was absolutely correct. He finally fished the needle from the sea.

The others on the airboat might never know that there was such a person with such an abnormal ability in this world. During the period of over 6 hours since they left Redmountain City, that person flew all the way from Dragon Emperor Big Domain to Nine Heavenly Big Domain; after that, it took him less than half an hour to find them among tens of thousands of airboats in the vast air territory from Redmountain City over 5,000 miles away——F*ck, what a freak!

Zhang Tie almost immediately arrived above the airboat. Being totally attached to the airboat, Zhang Tie started to check out the situation inside the airboat so that he could find an opportunity to save them…