Supersonic Movement Technique

Physicist Albert Einstein once said that every scale had its own laws.

Every theory had its range of applicability. Any correct theory, once it stepped even one pace beyond that range, turned into fallacy.

Of course, Einstein had originally been referring to the gulf between quantum mechanics and relativity. In the world faced by quantum mechanics, gravitational interactions were weak enough to be ignored, while in the vast universe faced by relativity, gravity was the mighty force that warped spacetime and ruled all. Describing the "macroscopic" and the "microscopic," "low speed" and "high speed," required different theories.

The "high speed" here was also "high speed" as physicists understood it—namely, "sub-light speed."

This referred to highly condensed theories crystallized from human wisdom.

As for humanity's intuitive experience, it was often even less reliable than theory.

The world "above the speed of sound" faced by cybernetic martial artists had already surpassed the grasp of human intuition and exceeded the preparations of evolutionary instinct.

Xiang Shan had no Vector Thruster, so the first problem he had to face was the challenge posed by fluid mechanics.

"Fluid" was a concept invented by humans. Nature had never decreed that something had to be a fluid or a rigid body. On the contrary, many objects possessed elements of both fluid and rigid bodies, displaying different properties under different conditions.

The first was "the duration for which force acted." If you slapped the surface of water hard, your hand would hurt. If you fell from a great height, the water's surface would be no different from a concrete floor. That was because your impact speed exceeded the speed at which the water could flow and dissipate force. When your hand made contact with the water's surface, what it displayed was not "the properties of a fluid," but "the properties of a rigid body."

The reverse was also true. Many things humans considered rigid bodies could display fluid properties over long periods of time. Rock, for example. Geological movement was the flow of rock. Before an immortal observer, mountain ranges flowed like water.

The second was "yielding." Some substances displayed fluid-like characteristics under immense external force. If you gripped a lump of modeling clay and squeezed hard, it would ooze through the gaps between your fingers. That was because the clay's "shear resistance" had "yielded" before the force.

Xiang Shan's running was like that.

He needed to keep kicking against the ground with immense force, but that force had already far exceeded the shear resistance the ground could possess. No matter how hard the earth was, under movement techniques of this level, it had no more backbone than rotten mud. At such speeds, striking the ground felt much the same as striking water.

The air before him was the opposite. He was simply too fast; the air had no time to "get out of the way." The front of his body kept crashing into the air, then passed beyond that mass of distorted gas before the reactive force could arise. Running through the air was harder for him than throwing punches amid ocean waves was for a natural-born boxer.

—Technique...

Xiang Shan kept roaring inside his mind.

He remembered this technique.

The angle at which he kicked off the ground could not be too shallow, because the outer armor of his prosthetic legs was not specialized, and its coefficient of friction was insufficient. Rumor had it that only materials capable of allowing a person to walk vertically along a wall could support supersonic movement without a Vector Thruster. To Xiang Shan, it felt as though his feet had been coated in lubricant...

The angle at which he kicked off the ground could not be too steep either. If he accidentally leaped up, changing direction in midair would never be as convenient as doing so on the ground. The moment both feet left the earth, he would become a target for the enemy's gun.

His speed had to be fast, because the faster he was, the lower his chances of being injured...

But he could not maintain top speed the entire time. A constant, unchanging speed could easily be predicted...

Xiang Shan thrust out his right hand and struck forward at a moderate speed. Layer upon layer of compressed air formed the barrier of a "shock wave" at just the right moment. In that instant, Xiang Shan's hand seemed to press against an invisible wall, changing his route through thin air.

If his punch had been even a little faster, the resistance from the shock wave at his side would not have been able to catch up to his arm.

Three bullets passed his crotch in succession.

—I saw the trajectory...

—The next shot... the correction parameters should be...

—Slow down...

A bullet struck the dirt in front of him. Under his ultra-high-speed vision, he saw the soil roll upward like waves.

—Accelerate again!

Atomized fuel was injected into the heat engine in his chest. The liquefied alcohol, thoroughly mixed with the atmosphere and oxidizer, combusted completely in an instant.

Unlike batteries that maintained constant maximum output, every heat engine created by humanity—including but not limited to steam engines, steam turbines, gas turbines, internal combustion engines, and jet engines—used the power of "explosions." They used the structure known as a "piston" to contain the "explosion" of atomized fuel and harness what had originally been an unrestrained "explosion."

Since this was not something necessary for sustaining life, there was no need to consider stable output, endurance, or even the engine's own service life... The engine's efficiency approached the theoretical limit of heat-engine efficiency without end.

This was precisely the kind of thing martial artists used.

Mechanical structures fed the gathered "explosions" directly into the mechanisms at his crotch. A cybernetic human's physical structure was distinctly different from that of a natural-born human; there was no such thing as "move one hair and affect the whole body." Every part of the body could generate force independently. A martial artist could choose to link all force into a single flow, or generate force in coordination.

Xiang Shan's speed suddenly surged.

Thus, seven bullets landed behind him!

Xiang Shan felt like a racing wild wolf, like an out-of-control motorcycle. The explosions between the pistons were like his heartbeat, and kinetic energy was his blood. In terms of bodily sensation, it was more like someone had stuffed a motorcycle into his heart.

That was perfect... because his fury truly was charging recklessly in all directions!

Directly ahead was a section of battleship outer armor wreckage. It was one of the few things that could serve as cover. Xiang Shan did not slow down and charged straight toward it. His tremendous speed pinned him against a plane nearly perpendicular to the ground.

His prosthetic legs slammed heavily onto the wall-like surface of the wreckage, and he ran sideways.

Five kilometers away, Geliad lost track of Xiang Shan. The drones could not keep up with that guy's movement. There were no drones around that area. But he did not stop firing. Instead, he fired twenty bullets at each side of that section of armor wreckage. The formation formed by those bullets would fly through the air for several seconds before biting into any target that might appear.

—Using that section of wall to change direction quickly? Is he trying to deduce my sniping position?

This was an asymmetric battle. Geliad was very confident. The long-range advantage of the Gunfire Way was also dictated by mathematics. He only needed to shift the muzzle a few millimeters, even a few micrometers, for the bullets' impact points to change drastically. No matter how fast a close-combat martial artist ran, he could not possibly be faster than a gunfighter moving his muzzle. The opponent could only rely on changes in speed like this to disrupt his predictions. Meanwhile, he could calmly keep moving the muzzle, weaving a trap of death with bullets.

This junkyard region was complex, and there was more than one area suitable as a sniping position. Geliad had even considered this when arranging the drone formation. He had deliberately left a small number of drones hovering in unimportant positions, so the enemy would misjudge his location.

—As long as that kid makes a mistake in his prediction, I'll gain roughly ten more seconds... No, even before that, choosing to use that vertical wall to accelerate and turn was a blunder. The moment your hands and feet leave the ground, the moment you show yourself, you won't have any chance to dodge.

But at that very instant, a silver glint flashed through his field of vision.

A section of armor wreckage resembling a city wall toppled over as though it had been struck by artillery. Yet in that brief interval, Xiang Shan merely ran at an angle for a short distance, crossed over the top of the wall, grabbed the edge of the armor wreckage with both hands, used the force to twist his body, then hugged his knees and somersaulted toward the ground.

"What..."

Gunfire rang out again. But the moment the bullet left the barrel, Geliad knew the shot had missed. The bullet would pass over Xiang Shan's current position several seconds later. The gunner immediately corrected the mistake, laying down an impenetrable net of bullets along that man's route of advance.

Then, the wreckage and Xiang Shan hit the ground almost simultaneously. Immediately afterward, the soaring cloud of dust completely cut off Geliad's vision.

But after that, every bullet missed.

—What happened?

The drone swarm had not captured any sign of him leaving. That guy seemed to have deliberately slowed down, leaving barely any disturbance in the dust. For the first time, Geliad appeared somewhat agitated. To him, the dust was like a natural enemy.

He had no idea whether he had hit Xiang Shan or not. All he could do was fire bullets one by one, blocking every possible route.

In this era, even sniper rifles could possess a high rate of fire.

But suddenly, a black shadow streaked across his field of vision. Geliad jolted and immediately switched his vision from long range to wide angle.

He saw the overall movement of the dust cloud.

That guy... had only just begun accelerating. He had stopped there for several seconds, then only now started accelerating again!

Bullets landed one after another in front of Xiang Shan. Those were bullets he had fired a second earlier. That martial artist was charging straight toward him, stepping on the tiny craters made by the bullets like he was running over waves?