After a week, he had worked through all the documents. There was no connection between the test subjects whatsoever. Nothing that gave away how they had chosen their guinea pigs in Soley. The oldest records dated back to the time when Dante had been transformed. Which at least meant they had very likely only started conducting the experiments with the onset of the war.
They had simply brought in soldiers—both their own and the enemy's. It didn't matter which side they had fought for. Anyone still alive was considered useful and turned into a test subject. And those already on the brink of death had, cruel as it sounded, simply been lucky.
What did earn a measure of respect from Helios, however, was the documentation. They had recorded a surprising amount—still not enough for his taste, but enough to piece together a picture of the procedures. The condition of the subjects had been noted, as well as age, gender, height, weight, and skin color. Even the origins of some patients were listed: civilian hospitals, hospices, places where life was already hanging by a thread.
Later, the data changed. The subjects grew healthier, more diverse—more random. Just as Helios had suspected, eventually everyone had been affected: men, women, children. Old, young. No one had been safe.
The experiments became more brutal, more unrestrained. People were strapped to tables. Those who resisted too much were "prepared," as one report cynically put it—physically destroyed to the point of barely being alive. The drug was even tested on perfectly healthy individuals. The records hinted at torments that defied description—and there was nothing to suggest the test subjects had in any way deserved such treatment.
But none of it had accomplished anything.
At least, the documents didn't reveal much more.
Helios was used to a lot. And he was no innocent one himself. But what they had done to the children rendered even him speechless. He didn't particularly like children—they were largely indifferent to him. Still, they were at the beginning of their lives, their futures yet unwritten. They hadn't yet been corrupted like most adults, shaped by their decisions. Children deserved protection. It was an unwritten rule. A line that no one should cross.
That alone made him hate his father just a little bit more.
He stared at Dante's file. Helios had just finished reading it and still stood before a nearly insurmountable wall.
He turned his gaze away and looked at Dante, who was silently flipping through personal notes in the warm candlelight. The flickering glow danced across his features, making them appear softer, almost kind—a stark contrast to the past few days, in which a wall of silence and defensiveness had grown between them.
Communication between them had become difficult, even though Helios had revealed one or two of his own secrets to him. Dante remained cold toward him. There was no longer any trace of the warmth he had shown him before their break-in at the underground lab.
Nights had become hard for Helios. Sleep came late, if at all. He still slept alone, while Dante squeezed himself night after night onto that uncomfortable, rickety cot that defied any notion of rest. Without coffee, he'd probably sleep the entire day.
Working under sleep deprivation wasn't unusual for him.
But somehow, this time it felt different. The more Dante ignored him, the more Helios wanted him to treat him like he had before Soley. Not that he showed it openly. He behaved as he always did—after all, he couldn't change who he was—but the desire was undeniably there.
Never before had he so desperately wanted someone to see him the way Dante had before Soley. He had always gotten what he wanted. So why the hell was it so damn hard this time?
But it was useless to get lost in that. The reality was brutally simple: once he found the antidote and had Belladonna in his grasp, Dante would disappear. Forever. And Helios would never see him again.
Helios scolded himself inwardly for letting his thoughts wander once more. He must have been more tired than he realized.
So what was different about Dante compared to the other test subjects? Helios could no longer run DNA comparisons; he couldn't compare blood samples, and Dante's already-altered body had yielded nothing in his initial analyses.
Was it the substances, then? If so, had it been a specific combination of those substances, which, together with Ambrosia, had made him immortal?
Next to Dante's file, he laid out the formulas from that time, ten years ago. He grabbed the substances that had, with considerable luck, been recreated according to the old recipes, along with the results of his analyses.
Helios had racked his brain endlessly, but nothing made real sense. So now, like it or not, he'd have to move into the testing phase.
He had reproduced the old formulas, his rats were ready, and now he just had to begin finding the right combination—if there was one at all.
There was enough Ambrosia for the rats and just enough left for a single dose—enough to make exactly one person immortal. Of course, that was pure speculation. He hadn't been able to find out anything concrete about Ambrosia, but hope, as they say, dies last.
The substance was odorless and colorless.
He hadn't dared to analyze it, as doing so would have required too much of the substance. So he knew nothing about its ingredients. The same applied to "PL-021." That substance was just as mysterious as Ambrosia, and he hadn't made any progress with it either.
The vial was old, and if the date could be trusted, the substance was nine years old. That made it highly likely that Dante had received it—even though there had been no documentation to confirm it. But since Helios didn't know what it contained, he couldn't reproduce it.
His gaze drifted over to Dante.
He sat there as always—silent, closed off, a living reminder of how much Helios still didn't understand. And how much he stood to lose.
"What's wrong?" Dante asked calmly. He had just looked up from Helios' notebook and was studying him with a questioning expression. His voice was steady, almost distant—but not cold. "You keep looking at me. Do you need help with something?"
Helios flinched, caught off guard. For a moment, he couldn't find the words. How was he supposed to answer that? He couldn't possibly tell the truth—that his thoughts had long since drifted elsewhere, that he kept wondering what it would be like if Dante simply stayed.
"You…" Helios began hesitantly, then let out a soft sigh. "You don't look like a Lucas."
Dante furrowed his brow. Surprise flickered across his face. "How do you know my name?"
Helios held out his single-page file. "They wrote down your data and what they gave you. Your name is in here, too. Did you change it because you didn't want them to find you?"
Dante stood up and took the documents about himself from Helios' hands. "Didn't think I'd ever hear that name again," he said quietly.
His expression was filled with pain. Absentmindedly, he ran his fingers over the paper. In that moment, Helios was once again reminded that Dante wasn't just five but fifteen years older. And if Helios didn't find an antidote, Dante would continue to age—trapped in the body of a twenty-seven-year-old.
"Do you want me to start calling you Lucas again?" Helios asked cautiously. He didn't know how to handle this situation.
Dante shook his head.
"Stick with Dante. Lucas is a name I'll only take back when I'm normal again," he said firmly. "So, how are things looking? The past few days, you've done nothing but bury yourself in those documents and barely said a word."
Helios sighed. Was that really how it seemed? To him, it felt more like the opposite—that Dante had shut himself off.
"The documents don't really tell me much. I know which substances they used back then, but not the actual dosage. There's just a list of substances, but no information on how many milligrams or milliliters. The vials are fairly small, so it's possible they used one full vial per compound."
Dante stepped over to the desk and studied the spread-out formulas, notes, and vials with a grim expression.
"And Ambrosia? Anything new?" he asked.
Helios shook his head. "Still a damn mystery," he said, then held out the vial labeled PL-021. "Just like this one."
Dante took the small, dusty bottle. "What is it?"
"I wish I knew. I found this vial in the treatment room—the same one where I found the other substances. It's quite old. Maybe even from the time when you were transformed."
Dante examined the vial thoughtfully, tilting it slightly against the light.
"You think they injected me with this?"
Helios shook his head. "I don't know. There's no mention of it in your records, and besides that, I haven't found any other trace of this PL-021 anywhere," he said, his gaze drifting over to the rats. He stood up with resolve. "I'm going to start the testing phase on the rats. Maybe we'll know more soon."
Dante looked at the rats with visible doubt.
"And what if the substances don't work on animals?" he asked, concerned. "What if we don't have enough to cure me? Are you really sure we should test on them?"
Helios sighed again. "Who else are we supposed to test it on? Me? No thanks, I don't plan on becoming a lab rat—especially not when I don't even know what the effects are."
"So you're unsure," Dante said grimly, running a stressed hand through his hair. "Goddamn it."
Helios shrugged. "If you don't want me to test it on the rats, say so. I'm open to suggestions—but honestly, I have no idea how else we're supposed to test the effects. We need to find the substance that makes someone immortal before we can even begin developing a cure."
"And who exactly do you plan to test it on? Even if it worked on rats, you wouldn't have a way to adjust the dose for a human," Dante snapped.
He looked incredibly stressed—and somehow, Helios could understand that. For Dante, this was probably his only shot at becoming normal again. Helios hesitated for a moment, then reached out and placed a tentative hand on Dante's shoulder.
"I was planning to test it on Belladonna," Helios admitted. "That's been my plan ever since he killed Davis… and since I learned your secret."
"On… Belladonna?" Dante repeated slowly. It seemed to take him a moment to process what Helios was saying.
"He's the perfect test subject, don't you think?" Helios said darkly. Just the thought of Belladonna made the cold rage rise in him again. "He has to pay for what he did to me. I can't just let him walk away. He has to suffer for his actions over and over—until I'm satisfied," Helios said grimly. "And besides, we'll know we've found the antidote when it finally kills him. I can't exactly keep killing you until it sticks."
Dante looked at him for quite a long moment. Helios feared that Dante would judge him for it—especially after what had happened in the underground complex. But to his surprise, Dante gave an approving nod.
"Maybe that's the only option we have."
Helios raised an eyebrow in surprise. "What, no moral lecture about how it's wrong to torture people?"
Dante shrugged. "That ship sailed for you a long time ago, didn't it? Besides, I want to see Belladonna suffer just as much as you do. Davis didn't deserve to die. It was way too early for him, damn it!"
Dante looked tormented, biting his lower lip as he turned his gaze away from Helios.
The two of them had been pretty close friends, Helios thought. For Davis, Dante had been a hero—he spoke so often and so fondly about him. Davis had been in much better spirits since Dante had joined them. More relaxed, more at ease, because he had someone who had his back.
Helios let himself fall heavily into his chair. For Davis alone, he had to make Dante normal again. He hadn't known about Dante's immortality, but to Davis, he had been a friend. Not that Helios hadn't already decided to help Dante—or ever wavered in that decision. But this gave him a different kind of motivation.
"Davis really liked you, you know?" Helios said quietly.
Dante looked at him in surprise again. A faint smile tugged at Helios' lips, even though he felt miserable thinking about Davis. It felt good to talk about him.
"He talked about you often, when we were alone. To him, you were a hero. He thought you were invincible. You should've heard him before you joined us—I wanted to shut him up so many times, the way he kept singing your praises," Helios said, with a tone of amused sarcasm.
To Helios' surprise, Dante smiled faintly.
"To me, he was more of a hero. I'm immortal—of course I don't go down easily. But compared to him…" Dante looked at Helios. "He dedicated his life to protecting you. To him, nothing was more important than making sure you lived. I've rarely seen someone so focused on a single goal like he was. When we were alone, he talked about you a lot. Davis loved you—deeply."
Helios' breath caught. The words struck him with a painful gentleness—like a familiar melody he hadn't heard in far too long.
A tear rolled silently down his cheek. He didn't even feel it until it was already on his skin. Davis had been dead for several weeks now, and this was probably the first time he was truly able to talk about the man he loved.
Quickly, he wiped the tear away, hoping Dante hadn't noticed.
He had loved Davis. More than anyone else in his life. And the loss still cut deep, even if daily life forced him into silence.
"Okay..." Helios cleared his throat; his voice was rough. "We'll use the rats just to compare the results."
He needed a new topic—desperately. He couldn't handle any more emotions right now.
With determination, Helios grabbed one of the substances he had reproduced. He set the vial down in front of him, picked up a blood collection kit, and without hesitation, drew his own blood.
He didn't know why he did it, or why he decided to do it so spontaneously. Maybe it was these strange feelings he had for Dante—the fear of loss that overwhelmed him every time he thought about their impending separation.
Or maybe it was just the exhaustion from a week of little to no sleep.
But whatever the reason, he wanted to help Dante return to normal. He would create this damn immortality serum—and then he would develop the antidote.
If that meant experimenting on himself a little, so be it. He had no intention of becoming immortal. It was unnatural and went against everything he stood for.
Life was supposed to be finite—and that's how it should remain. The anomaly that was Dante had to be corrected.
"What are you doing?" Dante asked, confused, as he noticed what Helios was doing.
Helios didn't answer. He set the vial of his blood aside, grabbed PX-209, and injected it into himself without hesitation. Of the three substances, it was probably the safest, since it was only meant to regenerate blood cells.
Even though all three compounds had more of an emergency-use character.
In fact, he assumed this one didn't just regenerate red blood cells—it also increased their production. It would make sense. The soldiers back then had very likely been brought into the underground complex while bleeding out.
He had reconstructed the compound carefully. He knew exactly what was in that vial, and if he had calculated everything correctly, the drug wouldn't harm him.
"Don't do it!" Dante's voice was full of panic as he realized what Helios had just done. He jumped up, trying to stop him—but it was already too late. The vial was empty.
Helios had injected the entire dose.
For a moment, there was only silence.
Dante stared at him in shock.
Helios' heart was racing. He was curious to see how the substance would affect him. He had tested substances on himself before—but only the ones he believed were truly safe. He felt a little warm, but other than that, there was no noticeable effect.
He didn't really expect to feel anything anyway.
Suddenly, Dante grabbed his wrist—tight, almost panicked—and tore the empty syringe from his hand. His eyes widened, his hand trembled slightly. The expression on his face was a mix of anger, fear, and complete overwhelm.
"Why did you do that, you damn idiot?!" he snapped at him. His voice nearly cracked, shaking with tension.
He set the syringe aside, briefly brushed Helios' cheek, his gaze locking onto Helios' eyes, feverishly searching for any sign that something was wrong.
"How do you feel? Do you feel anything? Does anything... feel strange? What exactly did you inject yourself with?! Damn it, Helios, say something—can I do anything?"
Helios placed a finger on his lips, silencing him. His guardian still looked at him with worry.
"It's okay," Helios said. "I'm fine."
Dante exhaled in relief, though his eyes remained full of concern.
"What did you inject yourself with?" he asked quietly.
"PX-209," Helios replied. "It's the compound that regenerates blood cells. So, by far the safest of all of them. I'm going to test it on the rats as well, so we can compare the results."
"Damn it... don't scare me like that!" Dante burst out, running a stressed hand over his face.
Helios shrugged. "It was a spontaneous decision," he admitted.
"You're never spontaneous. You plan everything five times over before doing anything," Dante said, still shaken.
"You're right." Helios nodded, then a thoughtful look crossed his face. "But I had an idea. PX-209 regenerates blood cells—which is basically exactly what your ability does. In all your samples, it's the only consistent anomaly. What if that was the crucial substance? What if that's the only one you really needed?"
Dante frowned. "Then the other two would be unnecessary. But I know they gave me all three."
"Because you were nearly dead back then," Helios replied calmly. "Maybe they only needed the other two to keep you alive—to stabilize you. PX-209 might be the actual source of your ability."
"What are you getting at?"
"Well, I don't think the other substances are useless. In a way, they do work. Even though I'd refine them—the formulas are far from elegant, and they definitely come with side effects. Since you were more or less a product of chance, I'm going to revise and enhance those formulas as well."
In that moment, Helios realized how close Dante had come. The other man was still gripping his wrist. His reddish-brown eyes were locked onto his, filled with concern—perhaps something else, too, something Helios couldn't quite place.
For the span of a heartbeat, time held its breath.
Helios cleared his throat softly and gently freed himself from the grip. He turned away, reached for another vial, and drew it up. Then he carefully took one of the rats from its cage, injected it with a tenth of the dose he had administered to himself, and placed it back. As a reward, he dropped a small piece of carrot into its bowl. The rat sniffed at it with interest.
Meanwhile, his thoughts continued where his voice had left off.
If the compound truly works the way the researcher described back then... then I'm holding the foundation of immortality in my hands, Helios thought as he carelessly tossed the rest of the syringe into the waste bin.
"If the compound really works as promised, then this is the first step toward immortality," he said aloud, leaning back slowly.
"We'll just wait and see what it does to me—and to the rat."
Dante crossed his arms, his expression skeptical. "And how do you plan to test the other two substances?"
"Honestly? I don't know yet. Testing on the rats would be the safest."
Helios grabbed his blood sample and examined it under the microscope, just as he had done with Dante's a few weeks earlier. So far, everything looked normal. He would test his blood again in an hour.
A sudden, piercing squeal made them both flinch. It came from the cage to Helios's right. He turned around, alarmed, afraid the animals might have attacked each other.
But only one of the rats was screaming. Its sounds grew shriller, then abruptly stopped. With a wet, squelching noise, its body grotesquely swelled—and burst. Flesh, blood - far too much blood for a rat- and organs splattered across the cage. The twitching, barely recognizable thing collapsed in on itself.
Helios stared into the cage, fascinated, while Dante made an indistinct noise. A headache was forming. Absentmindedly, he rubbed his temple. A large hand settled on his shoulder.
"Helios?"
He looked up, straight into Dante's shaken face.
"What is it?" Helios asked.
"Are you sure you're okay?" Dante asked with quiet urgency.
Helios frowned. It took him a moment to understand what Dante was getting at. Of course. He had injected himself with the same compound, but apart from a mild headache, he felt fine—no reason for concern. He still felt slightly warm, but that wasn't necessarily alarming either.
His gaze drifted back to the dead rat.
That could have been him.
"Looks like I got lucky," he said dryly. But Dante still looked worried. Helios sighed in irritation. "What?" he asked, annoyed.
Dante silently held out a cloth.
"You have a nosebleed."
Helios quickly cupped his hand under his chin as he felt the warm blood run past his lips and down to his chin.
"Damn," he muttered under his breath.