The lecture hall was fuller than Kai had expected.
Students packed the tiered seats—Support Track in the middle, Combat students lounging near the back, even a few General students scattered throughout. Word had spread about Holt's open lectures. People wanted to hear what the terrifying workshop instructor had to say when he wasn't threatening to fail them.
Kai sat near the front with Milo. His detection charm was tucked safely in his pocket, a constant reminder of what he'd achieved. Beside him, Milo's exoskeleton arm rested in his lap, disconnected from the harness but still humming with faint Aether.
"You think he'll mention anything about puppetry?" Milo whispered.
Kai shook his head. "Blood conductors. That's the topic. Probably focused on organic materials."
Milo nodded, disappointed but understanding. Then his expression shifted—something complicated flickering behind his eyes. "Kai... after the lecture, can we talk? It's important."
Kai studied him for a moment. Milo's usual nervous energy was different now—quieter, heavier. "Yeah. After."
The side door opened, and Holt walked in.
He didn't acknowledge the crowd. Didn't greet anyone. He simply walked to the front, set a stack of papers on the table, and began.
"Blood."
The word landed like a stone in still water.
"Every Aetherkin has it. Every core comes from something that bled. And every crafter who wants to work with organic cores needs to understand one thing." He paused, letting the silence stretch. "Blood is the best conductor."
Kai's attention sharpened.
Holt picked up a core blank from the table—standard starter grade, identical to the ones Kai had been carving. "You've all been taught to use resin. Resin works. Resin is cheap. Resin is easy." He set it down. "Resin is also wrong."
Murmurs rippled through the audience.
Holt ignored them. "Resin comes from plants. Plant cores resonate with plant blood—sap. Animal cores resonate with animal blood. Insect cores resonate with insect blood." He picked up another core blank. "When you use resin on an animal-derived core, you're forcing mismatched materials to work together. It will function. Barely. But you're losing efficiency."
Kai thought about his detection charm. He'd used resin. It had worked—G2 Stable, thirty feet, instant response. But if Holt was right, it could be better.
Holt continued. "Blood carries the creature's essence. Its resonance. Its memory. When you use blood as a conductor, you're not just connecting to the core—you're connecting to what the core was. The skill flows more naturally. The item responds faster. The efficiency increases."
He wrote on the board in quick, sharp strokes:
Organic core + organic blood = optimal conductivity
Organic core + plant resin = acceptable, but inefficient
Mineral core + liquefied crystal = optimal
Mineral core + anything else = failure
Kai copied it into his notebook, his hand moving automatically.
A Combat student near the back raised a hand. "Instructor, where do we get blood? We can't just... bleed Aetherkin whenever we want."
Holt's eyes found him. "You hunt. You harvest. You buy from those who do." His voice was flat. "Or you bond with a living creature and take small samples without harming it. That's harder. That requires trust."
Kai's heart beat faster.
A living creature. Small samples. Without harming it.
He had a living creature. A Signal Gnat, bonded to his core, resting in the Hive Core Realm. If he could take a tiny amount of its blood—just enough to test—he could improve his detection charm. Maybe even build the Pingband.
Holt moved on, discussing specific ratios, extraction methods, and preservation techniques. Kai took notes furiously, capturing every detail. The ideal blood-to-resin mixture for stability. The temperature range for storage. The signs of spoilage and contamination.
An hour passed. Then another.
When Holt finally stopped, the board was covered in diagrams and formulas. The audience sat in stunned silence, overwhelmed by information.
Holt set down his chalk. "Questions."
No one spoke.
Then Kai raised his hand.
Holt's eyes found him. "Entoma."
Kai stood. "Instructor, you mentioned bonding with a living creature. Taking small samples without harming them. How small is safe? How do you know when you're taking too much?"
The room went quiet. Students stared at Kai like he'd grown a second head.
Holt studied him for a long moment. Then: "Follow me after class."
He turned and walked out.
Kai found Holt in his workshop, organizing core blanks by grade. The room was empty except for the two of them.
"You have a bonded creature," Holt said. Not a question.
Kai hesitated. Then: "Yes."
"Insect?"
"Yes."
Holt nodded slowly. "That's rare. Especially for a first-term." He set down a core blank and turned to face Kai. "The answer to your question depends on the creature's size, its tier, and your relationship with it. A Tier 1 small insect can spare a single drop every few weeks without harm. A Tier 1 bigger insect, maybe two drops. Any more than that and you risk weakening it."
Kai filed that away. "How do you collect it without hurting it?"
"Patience. Trust. A needle fine enough to barely pierce the exoskeleton." Holt paused. "And you let it heal afterward. Feed it. Rest it. Treat it like a partner, not a resource."
Kai nodded slowly. "That's what you did? With your micro-constructs?"
Holt's expression flickered—surprise, maybe, or something else. "You've heard about that."
"A senior student named Senn told me. Said you were General Track. Struggled. Invented micro-constructs and became an instructor."
Holt was quiet for a long moment. Then he walked to a cabinet and pulled out a small box. Inside, nestled in cloth, were tiny figures—insect-sized, delicate, carved from something that shimmered faintly.
"These were my first successes," Holt said. "Took me three years to get them right. Ruined hundreds of cores. Wasted thousands of credits." He picked one up, held it to the light. "I was General Track. No one expected anything from me. I expected everything from myself."
Kai stared at the tiny constructs. They were beautiful—intricate, precise, alive with faint Aether.
"I used blood," Holt continued. "From creatures I'd bonded. Took years to earn their trust. Years to learn how much I could take without hurting them." He set the construct back in the box. "That's why I teach. Because I remember what it felt like to have no one to ask."
Kai didn't know what to say.
Holt closed the box and put it away. "You're on the right track, Entoma. Detection charm, G2 Stable, thirty feet—that's good work. But blood will make it better. Find a way to get it without harming your partner. That's your next challenge."
Kai nodded. "Thank you, Instructor."
Holt waved him off. "Go. Sleep. You look terrible."
Kai almost smiled. He turned to leave, then paused. "Instructor—why did you become a teacher? Instead of building your own faction, your own army?"
Holt was quiet for a moment. Then: "Because I've seen what happens to people who only care about power. They end up alone." He looked at Kai. "I'd rather watch students fail and get back up. I'd rather see someone like you figure it out and know I helped." He almost smiled. "That's worth more than any faction."
Kai walked out with his head full of new knowledge and his heart lighter than it had been in weeks.
He found Milo waiting in the workshop, sitting at his station with his exoskeleton arm disassembled in front of him. His face was pale, his hands fidgeting with a loose screw.
Kai sat down. "You wanted to talk."
Milo nodded slowly. He didn't look up. "That detection charm you made. The G2 one. The one that actually works."
Kai waited.
Milo's voice dropped. "My sister is eight years old. Her name is Lena."
Kai listened.
"She's small. Too small. Always been sickly." Milo's voice cracked. "When the breach happened—when those Aetherkin got into the city—she was home alone. Our parents were both at work. She hid in a closet for three hours, listening to things scratch at the door."
Kai's chest tightened.
"She doesn't sleep anymore. Not really. She just lies there with her eyes open, waiting for something to break in." Milo looked up, and there were tears on his face. "I'm here, in the academy, learning to make things, and she's at home scared out of her mind every night."
Kai didn't speak. There was nothing to say.
Milo wiped his eyes. "I know you're working on the Pingband for your family. I know that's your priority. But if you ever have time—if you ever make another charm, even a small one—I'd do anything. I'd pay anything. I'd—"
"Milo."
Milo stopped.
Kai looked at him steadily. "I'm not giving you the G2 charm."
Milo's face fell. "I understand. You need it for—"
"I'm going to make you a G3."
Milo stared.
Kai pulled out his notebook, flipping to the pages filled with Holt's lecture notes. "Blood conductor. Gnat blood. If I can make it work, the efficiency jumps. The detection range increases. The response time becomes instant." He looked at Milo. "I'm going to make one for Lena. The best one I can build."
Milo's mouth opened. Closed. Opened again.
"B–but your family—the Pingband—"
"My family too." Kai's voice was quiet but firm. "That's exactly why I understand. If it's for family, you don't half-ass it. You don't give them something crude and hope it's enough." He tapped the notebook. "Holt just gave me the key to making these better. I'm going to use it. For my family. And for yours."
Milo's eyes were wet again. "Kai, I—"
"Give me time. I need to figure out the blood extraction. I need to practice. I need to not hurt my gnat in the process." Kai leaned back. "But when I'm ready, I'll make two first. One for my mother, one for your sister. And they'll be the best I can make."
Milo didn't speak. He just sat there, tears streaming down his face, nodding.
Kai stood. "We look out for each other. That's what this is."
He walked toward the door, then paused.
"Oh, and Milo? That G1 charm I made—the crude one. I'm keeping it. It's a reminder of how far I've come." He glanced back. "Your sister deserves better than a reminder. She deserves something that actually works."
He walked out, leaving Milo alone with his tears and a new kind of hope.