Chapter 30: Bullets, Constraints, and the Acheron Moment

(Page 1 of 3)

“Bullet Time is the period during which a Mercury Needle can enter a heightened combat state. The length of time each Mercury Needle can maintain that state varies... You already knew that, didn’t you?”

Hesta nodded.

“Good,” Chiba continued. “Once they enter Bullet Time, Mercury Needles can’t simply relax. We have to keep ourselves in that state—just as you would clench your fists when fighting someone.”

Following Chiba’s demonstration, Hesta clenched both hands into fists. But in the next instant, Chiba suddenly drew her gun again and fired at the target in the distance.

The deafening report of the shot exploding from the barrel caught Hesta completely off guard. She instinctively covered her ears—though too late.

Chiba laughed. “There are always unexpected incidents that can make someone forget to ‘clench their fists,’ just like your reaction now. Maintaining Bullet Time is much the same. For a Mercury Needle, however, the moment we forget to maintain our state, we rapidly fall out of Bullet Time and enter Constraint Time.”

“Constraint Time...” Hesta murmured, repeating the term.

“Think of it this way: once a car has started, you can step on the accelerator to speed up or turn the wheel to change direction whenever you like. But if the engine stalls midway, you have to spend time starting it again. During that process, your car is no longer a nimble tool for getting around. Until the engine restarts, you can hardly use it for anything at all. A Mercury Needle’s body works the same way.

“Once a Mercury Needle enters Constraint Time, they become weak and powerless. During that period, forget fighting—even standing upright on their own is difficult.

“For example, suppose a Mercury Needle has a Bullet Time of roughly ten hours. During a particular operation, they choose to take a temporary break after working continuously for no more than five hours. They would then typically experience a period of weakness lasting anywhere from ten to twenty minutes.

“During that time, they can do nothing. Only after the Constraint Time ends can they reenter Bullet Time. We call this kind of situation ‘Partial Constraint Time.’”

Hesta considered this. “Then there’s also ‘Full Constraint Time’?”

“Exactly,” Chiba said with a smile. “Using the same example, if that Mercury Needle works continuously for more than five hours, then the moment they stop, they enter Full Constraint Time directly.

“Full Constraint Time generally lasts half as long as Bullet Time. Whether that Mercury Needle worked continuously for six hours, seven hours, or ten hours, once they stop, they have to lie still for five full hours before they can move again.”

Hesta furrowed her brow in deep thought. “I see.”

(Page 2 of 3)

“Have you ever wondered how the length of Bullet Time is determined?”

Hesta tilted her head slightly. “Through some kind of... endurance testing?”

“More or less,” Chiba said with a laugh. “The so-called Second Special Training is conducted in a controlled location. Active Mercury Needles are responsible for releasing chelates against recruits who have not yet undergone their Second Awakening. During the battle against the chelates, the recruit’s Bullet Time awakens naturally. The others are there to time it.

“...Until Bullet Time fails?”

“It’s not as simple as failure,” Chiba said softly. “When a Mercury Needle approaches their physical limit, their abilities undergo an extraordinarily powerful burst. On top of their original Bullet Time, their strength increases by another twenty to one hundred and fifty times. But this usually lasts only from several dozen seconds to a few minutes, at the cost of self-destruction. Once it ends, the person suffers massive internal bleeding and systemic organ failure, just as a chelate does when it dies naturally.

“That final burst is the Acheron Moment.” Chiba’s voice softened. “Bullet Time is calculated from the moment you enter combat status until the Acheron Moment arrives and ends.”

Hesta suddenly spoke. “Is that... why the base requires Bullet Time to exceed four hours before someone can participate in combat?”

“Mhm.” Chiba nodded lightly. “Setting aside a few extreme cases, it takes a squad of around five Mercury Needles an average of fifty-seven minutes to hunt a single chelate. A Bullet Time of less than four hours is simply too dangerous on the battlefield. Never mind the Acheron Moment—once you enter Constraint Time, even a five- or six-year-old child could easily slit your throat with a knife.”

Only then did Hesta suddenly understand many things that had happened in the past. For instance, on the night Rigo participated in special training, she had ended up in the base’s underground hospital because of her severe injuries.

At that thought, Hesta suddenly realized something. “...But chelates usually survive for only two weeks to a month. How does the base ensure that enough of them are available for special training? Do they capture them on demand?”

“Ah, now that’s information of a higher security classification.” Chiba smiled brightly. “You can think it over yourself if you like, but you must not tell anyone else anything I’ve told you today. Can you do that?”

Hesta nodded solemnly.

“Now, back to Sean. Listen carefully,” Chiba continued. “His Bullet Time is four hours and fifty-five minutes, and his Intermittent Constraint Time is twenty-two minutes. In other words, if he enters Bullet Time and you interrupt it, you’ll have at least twenty-two minutes to do whatever you want.”

“But how am I supposed to—”

“Generally speaking, the stability of Bullet Time is related to the person’s will to fight. Do you remember the question I asked you last time?”

(Page 3 of 3)

Hesta fell into deep thought.

“As for exactly what you should do,” Chiba continued, “you’ll have to figure that out yourself.”

“...I understand.”

Chiba let out a quiet breath and turned to look at the distant targets. “Would you like to practice a few more rounds today? I’ll have to take you back in another hour.”

“Does Miss Chiba have something else to do this afternoon?”

“Not particularly, but Molly only approved half a day for me.” Chiba spread her hands. “As you’ve seen, these are extraordinary times. Your photographs are all over the place outside. Letting you wander around with me for an entire day really wouldn’t be very convenient.”

Hesta lowered her eyes and thought for a moment. “Then can we keep practicing today? I can explain things to Director Molly myself.”

“Sure.” Chiba smiled. “Then I’ll go get a few more boxes of ammunition.”

...

Inside the base, in Sophie Molly’s office, Liz stared at Director Molly in shock. She rose to her feet, her voice edged with agitation.

“Why are we suspending the investigation into Sean now?”

“We will investigate this matter to the very end,” Molly said calmly, looking at Liz. “But we haven’t found any evidence in his equipment, have we?”

“You also believe that Sean was responsible for the power outage in the grammar classroom and the missing surveillance footage—”

“Yes.” Molly’s voice grew heavy. “But continuing the investigation now will only give people with ulterior motives an opportunity to exploit it.”