Six hours later:
The integration was holding beautifully.
Reven had spent the time testing his new capabilities. The flame generation was controllable—he could produce anything from a candle's warmth to forge-level heat. The scales were nearly as hard as steel. And most importantly, his entire body's heat resistance had increased dramatically.
He could hold his right hand in his left's generated flame without injury. Being able touch metal he'd heated to glowing without burning. Stand next to the forge's hottest section without discomfort felt pleasurable.
This was what he needed for the Colossus hunt. The ability to survive in environments that would kill normal hunters. The capacity to channel heat rather than just endure it.
But the hunger was already returning. Stronger than before. The integration was burning through his essence reserves at an alarming rate. His Essence Load had dropped from 19.2% to 14.7% in six hours just maintaining the flame organ's existence.
He'd need to feed soon. Consume more materials. Keep the hunger at bay.
Later.
First, he wanted to see if the flame generation could actually improve his smithing—
The workshop door opened.
Reven spun, instinctively raising his left hand. Heat gathered, ready to—
"Whoa!" Lysa held up her hands. "It's just me! Don't incinerate the Keeper!"
Reven lowered his hand, willing the heat to dissipate. "The door was locked."
"I have master keys. Perks of maintaining the Aegis infrastructure." She stepped inside, closing the door behind her. Then she saw his arm. "Oh. Oh."
The scales were impossible to miss. They caught the lamplight, reflected it in crimson patterns across the walls.
"You integrated it," Lysa breathed. "The flame sac. You actually integrated it."
"Yes."
"That's..." She circled him, studying the scales with a scholar's intensity. "That's insane. That's brilliant. That's terrifying." She looked at his face. "How do you feel?"
"Powerful. Hungry. Unstable." Reven flexed his scaled hand. "The integration will reject in about two hours. The System warned it's going to be extremely painful."
"Can you survive it?"
"I don't know."
"That's why I'm here." Lysa pulled out a small notebook. "I've been studying your essence signature since you arrived. The way it resonates with Calamity-class energy. And I noticed something during today's council meeting."
She flipped to a page covered in sketches and calculations.
"Your crimson veining—the visible manifestation of the Calamity blood—it pulses at a specific frequency. 7.3 beats per second, split into seven overlapping rhythms. That number seemed familiar, so I checked the heartstone's output patterns."
She showed him a diagram. The heartstone's energy fluctuations. His own cardiac rhythm. Overlaid on the same graph.
They matched.
"Your blood," Lysa said quietly, "is resonating with the heartstone. Not perfectly—there's interference, probably from the corruption. But the fundamental frequency is identical."
Reven stared at the diagram. "What does that mean?"
"I don't know. But I have a theory." She looked at him. "What if Calamity-class entities and heartstones are connected somehow? What if heartstones were designed—or evolved—to channel the same type of energy that entities like Vyraxes embody?"
"That's a big leap."
"Is it? Think about it. Heartstones protect us from monsters. But they also attract essence. Concentrate it to make it usable." She tapped the diagram. "What if they're not just barriers? What if they're converters? Taking raw Calamity-level energy and making it stable enough for human use?"
"And you think I can—what? Feed energy into the heartstone?"
"Maybe. Or maybe you can help me understand how to make it more efficient. How to stop it from failing in the future." Lysa's expression was intense. "Reven, if you can resonate with Calamity energy and survive... you might be the key to fixing what's wrong with our heartstone."
Before Reven could respond, pain lanced through his chest.
Not gradual. Not building.
Immediate.
He collapsed. Hit the floor hard. His scaled arm convulsed, the flame organ inside his chest was trying to exit, trying to reject integration with the host body it had merged with.
"Reven!" Lysa dropped beside him.
His back arched. The scales began to crack, flaking away in burning fragments. His skin underneath was blistered, raw, weeping fluid that steamed in the cool air.
The heat inside him had nowhere to go. The flame organ was rejecting, but it wasn't leaving—it was just breaking down inside him, releasing concentrated fire essence directly into his organs.
He was cooking from the inside out.
"Stay with me! Don't you dare die after proving me wrong about you!"
Reven tried to speak, but couldn't. His throat was full of smoke. His lungs were full of heat. His body was trying to decide if it wanted to be human or a forge and settled on neither.
Darkness crept in at the edges of his vision.
This is it, he thought distantly. I pushed too far. I integrated too much. I'm going to die in a workshop. Like my master would have wanted. Surrounded by tools and half-finished work.
The darkness closed in.
And then—
Something shifted.
The Calamity blood in his veins, dormant until now, reacted. Not to the pain. To the rejection.
It surged. Immediately wrapping around the breaking flame organ. It didn't force it to stay integrated—that would have killed him. Instead, it guided the rejection. Controlling it, which made its dissolution gradual instead of catastrophic.
The scales fell away. The heat dissipated. The flame organ's essence bled out through his pores in slow, controlled waves.
Reven vomited blood. Crimson, steaming, wrong.
Then passed out.
He woke in the medical ward.
Lysa sat beside his cot, looking exhausted. When she saw his eyes open, relief washed over her face.
"You're insane," she said.
"No," Reven rasped. His throat felt like he'd swallowed glass. "I'm adapting."
"To what?"
"To being something else."
Lysa helped him sit up. His chest was bandaged, but he could see the crimson veining beneath the wrappings. Still there. Still pulsing in that seven-rhythm pattern.
"You almost died," she said quietly. "The rejection was worse than the integration. If your blood hadn't stabilized the process..." She didn't finish.
"But it did."
"Yes. Which raises questions I don't have answers for." She pulled out her notebook again. "While you were unconscious, I monitored your essence signature. During the rejection, your blood actively channeled the excess energy. Not just dissipated it—channeled it. Like it knew what to do with Calamity-level essence."
"Maybe it does. It came from Vyraxes. Maybe some of that knowledge... transferred."
"That's terrifying."
"That's useful." Reven swung his legs off the cot. Stood slowly. His body protested, but it obeyed.
"How long was I out?"
"Six hours. It's almost dawn."
"Then I need to get back to work. We have seventy-eight days until—"
"Sit. Down." Lysa's voice was sharp, pushing him back onto the cot. "You just survived a catastrophic integration rejection. You need rest and recovery. Not more experiments."
"I don't have time for—"
"Reven." She grabbed his arm. Not hard. But firm enough to make him stop. "Listen to me. What you're doing? Integrating high-grade materials? That's not sustainable for you at this time. Every integration damages you. Pushes you further from human. Eventually, you won't be able to come back."
"I know."
"And you're doing it anyway?"
"Yes." He met her eyes. "Because the alternative is everyone here dies when the heartstone fails. I can handle temporary integrations. I can survive the rejection process—barely. And if that's what it takes to hunt the Colossus and get the materials we need, then that's what I'll do."
Lysa was quiet for a long moment. Then she sighed.
"You're absolutely insane."
"You've told me that already."
"But you're also right. We don't have better options." She released his arm. "Fine. But we're doing this smart. I'll help you. Study your integration patterns. Figure out how to minimize the rejection damage. Prepare medical interventions for when things go wrong."
"Why?"
"Because someone has to make sure you don't kill yourself before you kill the Colossus." She looked at him. "And because... during your integration, while you were unconscious, I noticed something."
"What?"
"Your blood. The crimson veining." She gestured at his bandaged chest. "It was pulsing in perfect rhythm with the heartstone's fluctuations. Not approximate. Perfect. Like they were synchronized."
Reven processed that. "You really think I can interact with the heartstone directly."
"I think you might be able to do more than interact with it." Lysa's expression was intense. "What if you could feed energy into it? Reinforce it? Instead of just repairing the crystal with Colossus materials, what if we could strengthen it using your blood?"
"You want me to become a battery."
"I'm suggesting you might be the only one who can..." She pulled out her diagram again, showing the matching frequencies. "Standard heartstone repairs just replace degraded materials. But if you can channel Calamity-level energy the way your blood does during integration... we might be able to do more than repair. We might be able to upgrade."
Reven looked at the diagram. At the perfect synchronization between his cardiac rhythm and the heartstone's pulse.
"That's a theory," he said carefully. "Unproven. Dangerous. As you'd say"
"All the best ideas are." Lysa smiled slightly. "But think about it. If it works, Haven's Reach won't just survive, it will thrive. We'd have the most stable heartstone in the region. Maybe stable enough to attract new residents. Rebuild what was lost from ancestors forgotten even to pen and paper."
"And if it doesn't work?"
"Then we stick with Plan A: hunt the Colossus, get the shards, repair what we can, and hope it's enough." She stood. "But at least we'd have tried."
Reven considered it. The pain of the rejection was still fresh. His body was damaged, exhausted, pushed to limits that normal humans couldn't survive.
But he'd survived. And learned.
And now there was a possibility—however slim—that he could do more than just repair. He could improve.
"Let me think about it," he said finally. "After we prepare for the Colossus hunt. After we have backup plans. Then... maybe we test your theory."
"Fair enough." Lysa headed for the door. "Get some rest. Real rest. That's an order from your Keeper."
"I'm not part of your staff."
"Consider yourself deputized then." She paused. "And Reven? Thank you. For trying. For risking yourself. It matters."
She left.
Reven sat on the medical cot, alone with his thoughts and the fading pain of rejection.
His left arm still tingled where the scales had been. His chest still ached where the flame organ had nearly killed him.
But he'd proven something important: major integrations were possible.
Painful. Dangerous. But possible.
And if he could survive a Scorchwing Alpha flame sac, he might be able to survive what he'd need to hunt a Mantle Colossus.
Might.
The word hung in his mind like a promise and a threat in equal measure.
He laid back down. Closing his eyes, allowing himself to peacefully sleep.
Tomorrow, he'd start preparing in earnest. Study the Colossus. Plan the hunt. Build the equipment.
Tonight, he'd rest. And dream of forge-fires and scales and heat that didn't burn because it was part of him.
And maybe—just maybe—dream of a future where Haven's Reach survived because he'd been broken into the right shape to save it.