Faced with Zhang Tianran's hands-on lesson, Barry Allen had not paid attention at all. He simply went over and freed Martin Stein from his restraints, without even using the Speed Force.
"Ah... forget it. You've suffered enough losses already. You'll probably learn your lesson on your own." Seeing this, Zhang Tianran completely lost interest in continuing his lesson.
"Barry, take Professor Stein and leave first. I still have some cleanup work to deal with." Since he no longer intended to teach, Zhang Tianran sent Barry away.
Barry nodded at those words. He immediately hoisted Martin Stein over his shoulder and left without wasting a moment.
Only after Barry had completely vanished did Zhang Tianran activate Speed Mode, storing the remnants of Barry's Speed Force within his body for future research.
Afterward, he went to the military base's archives to see whether there was anything there that interested him.
Generally speaking, military equipment was several levels ahead of civilian technology. But in this world, the gap did not seem so obvious.
He found a few interesting toys, but gained little else. Zhang Tianran left somewhat disappointed, without killing anyone.
Although that so-called General Eiling definitely would not let the matter rest if Zhang Tianran spared him, killing him offered no great benefit and would instead cause trouble.
So, whatever. The military in this world had some strength, but it was not particularly important.
Barry brought Martin Stein back to STAR Labs, and Caitlin immediately began treating his injuries.
Although the military's interrogation had only been half completed, it was still a severe burden for an old man, even if Martin Stein was no longer merely himself.
While Martin Stein's wounds were being treated, Zhang Tianran said:
"I found a drug that can temporarily suppress both of your abilities, but there is currently no way to completely eliminate your supernatural powers."
"However, according to my calculations, the two of you can actually separate now. You only need to merge once more, then inject the drug I made."
Upon hearing this, joy immediately appeared on both Martin Stein's and Ronnie Raymond's faces.
If possible, neither of them truly wanted to become a Metahuman.
"Really? Ronnie can return to being a normal person?" Caitlin asked in disbelief.
Zhang Tianran shook his head and explained:
"No. I only said that I can let you separate completely and temporarily conceal your supernatural abilities. The original changes will not disappear. If you wish, you can become Firestorm at any time, but you will need certain equipment to assist you then."
Just as Caitlin grew disappointed, Zhang Tianran spoke again:
"Although the physical changes cannot be undone, living a normal life will not be a problem. After all, the two of you can only become Firestorm when you are together."
Martin Stein seemed to finally understand Zhang Tianran's meaning. "You mean the changes to our bodies caused by the Particle Accelerator explosion cannot disappear, but you can let us separate completely?"
"Yes, that's right..."
In the end, Martin Stein and Ronnie Raymond chose to separate completely. As for whether they would continue living as Firestorm afterward, neither had decided yet.
After all, the government military already had its eyes on them. Living a normal life was no longer going to be so simple.
Everything seemed to settle back into an ordinary daily routine.
Zhang Tianran continued working in his newly renovated private laboratory, while Barry and the others kept watch over all of Central City, occasionally catching thieves or rescuing people trapped in fires.
More than a week passed in a flash. Just as Zhang Tianran was wondering why the change Reverse-Flash had mentioned had yet to arrive, everything happened with startling suddenness.
As usual, Zhang Tianran was making little toys in his private laboratory when Caitlin's voice came through the emergency channel.
"Dr. Zhang, Barry needs help..."
But in the next instant, everything around him froze, just as it did when Zhang Tianran used the Speed Force.
Except this time, Zhang Tianran was certain that he had not used any Speed Force.
Soon, the frozen world began moving again, but instead of continuing forward, it was rewinding...
Before long, time's rapid retreat completely shattered everything. Like someone forgotten by time itself, Zhang Tianran could only watch as everything vanished before transforming into another scene.
This was... a change in the timeline.
Turning into a streak of white lightning, Zhang Tianran immediately found Barry Allen. Although he had already anticipated it, he still asked, "Barry, what did you do?"
"Dr. Zhang, I... I don't know. Just now, I was stopping a tsunami from destroying Central City, but now..." Barry instinctively glanced at the dark street, utterly confused.
"Barry, what happened? I saw you stop..." Cisco's voice came through the communicator, leaving Barry even more puzzled.
"Stop? Where am I supposed to go?" Barry became even more unable to make sense of what was happening.
"To the morgue. Weren't you going to inspect the crime scene?" Cisco asked, confused.
"Didn't I already go yesterday? Why is it now..." Before Barry could finish, Zhang Tianran directly pulled him into Speed Mode.
"Dr. Zhang..." It was Barry's first time being pulled into such a state by someone else, and he felt somewhat uncomfortable.
"Barry, listen carefully. I don't know what happened to you, but you have clearly crossed through the timeline. Or rather... this is not ordinary time travel. You have turned time back to last night."
Without stopping to understand what he had just experienced, Zhang Tianran immediately told Barry Allen, "Remember this. From now on, do not change anything. Even if you know everything, you must still do exactly what happened yesterday."
"Do not play with time. Any attempt to alter the timeline will bring an even greater tragedy."
"Forget it. You probably won't listen. But this is an experience. Remember what happened this time, and then... never try to change the past."
Although he knew Barry was very unlikely to listen, Zhang Tianran still gave him a warning. Then he turned into a streak of white lightning and vanished.
"Wells, I need to talk to you." After returning to STAR Labs, Zhang Tianran immediately sought out Reverse-Flash, who sat in his wheelchair with a grim expression.
Wells glanced at Cisco beside him, then controlled his wheelchair and left with Zhang Tianran.
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