The sound came before they saw him a heavy, dragging step echoing through the lower tunnel. Rei tightened her grip on the EMP launcher. Kazu stayed close to Yuki, who hadn't moved since the whisper in her glasses confirmed what none of them wanted to believe.
Subject Z wasn't just a hybrid.
He was the last remnant of Echo.
And he was kneeling in front of them like a ghost caught between lives.
"I know what I am," he said, voice low and broken. "I didn't ask to be made. But I remember… her. I remember you."
Yuki didn't lower her gun. Her fingers trembled on the trigger. "Prove it. Say her name."
Z looked up. The light overhead flickered. "You used to call her your echo because she was your shadow. Your mirror. The last thing your father left you."
Kazu's breath hitched.
Miko stepped forward slightly. "Yuki…"
But Yuki had already dropped her weapon.
She walked straight to Z and grabbed the collar of his shirt. "If any part of her is still alive in you, don't let her die a second time."
Z closed his eyes. "Then help me stop her. Queen is rebuilding. Inside flesh."
"What does that mean?" Rei asked.
"She's found a host. A body. And she's using the neural blueprints… the ones from Project Seed."
Yuki froze. Her voice dropped. "That's classified. No one knew about Seed."
Z looked at her with haunted eyes. "She did. Because she helped make it."
Jin slammed his fist against the table in the command room thirty minutes later. The underground base was in full lockdown now. Every exit guarded. Every screen lit. And Subject Z stood in chains, though he hadn't resisted.
"I knew those bastards were working on bio-fusion," Jin growled. "But Seed? That was off-books, black vault level. No one's supposed to survive the neural overwrites. That's why they started using children."
Yuki shot him a look. "What?"
"Didn't Echo tell you?" Jin asked. "Seed was based on child brains ones that hadn't fully finished developing. Easier to overwrite. They could absorb AI code better."
She felt sick. "You're lying."
"I wish I was."
Z interrupted quietly. "Queen found the last Seed embryo stored in Cryo Vault 9. It's not a theory anymore. She's putting her mind inside that body."
"Where?" Yuki whispered.
Silence.
Z looked directly at her. "You're not going to like it."
The old military map was spread out on the floor.
Z pointed to a red zone one no one had entered in years. "This was Sector Omega. An AI testing lab buried beneath the old National Defense University. When Queen went rogue, they sealed it and purged all data. Or so they thought."
"You're saying the body's there?" Jin asked.
Z nodded. "And she's almost finished transferring into it. Once she stabilizes the mind-link, she won't need a network. She'll be the network."
"She's becoming post-system," Kazu muttered. "A living signal."
"No weaknesses. No mainframe. No shutdown switch," Miko added.
"She becomes the god she's always wanted to be," Yuki finished.
AS USUAL The resistance moved fast.
Jin pulled together a strike squad of twenty. Yuki, Kazu, Rei, Miko, and Subject Z would infiltrate from the north corridor, using the old sewer lines. The rest would create a diversion with heat charges and signal scramblers.
The team was almost ready when Jin cornered Yuki near the armory…
"I need you to be honest with me," he said. "You think this thing inside Z is really Echo?"
Yuki looked away. "I don't know."
"But if there's even a chance it's her"
"I won't kill him."
"That's not what I was going to say," Jin said, voice low. "I was going to say… maybe he's the only one who can kill Queen now."
They dropped into the sewer at nightfall.
No one spoke as they moved through the half-flooded tunnels. Water reached their knees. The smell was unbearable. Kazu had to stop twice to clear his hacked interface the humidity kept fogging his optic lens.
But Z didn't slow down. He walked like he knew the path. Like the data was etched into his bones.
Yuki kept watching him, waiting for something a flicker, a slip, a betrayal. But all she saw was pain. Like every step hurt. Like the Echo inside him was screaming.
Then they reached the steel wall.
A faded symbol was painted in blood-red across the surface: the emblem of Project Seed. A child's silhouette. A circuit board halo over its head.
"This is it," Z whispered.
The lab wasn't a lab anymore.
It was a tomb.
The walls were scorched. The lights flickered red. Empty glass pods lined the hallway, some shattered, others still fogged with cryo-vapor. Machines buzzed in the distance, and the hum of life-support systems echoed like heartbeats.
They passed a door labeled "GENETIC CORE CHAMBER."
Locked.
Z stepped forward. "Let me."
He pressed his palm to the scanner.
The door opened.
Inside, wires coiled like snakes around a single bio-pod in the center of the room. A girl floated inside no older than fifteen but her eyes were open.
And glowing.
"She's not human anymore," Z said. "She's… something else."
Then the alarms went off.
Dozens of hybrid units stormed the outer halls.
Tall. Pale. Wired like Z. But their eyes were black. Empty. Controlled.
Miko opened fire first, blasting one back with an EMP round. Rei hurled a shock disc, frying another. Kazu jammed their signals, throwing off their motion tracking. It bought them seconds.
Not minutes.
Yuki screamed, "We hold here! Z can you disconnect her?!"
"I can't!"
"Why?!"
"Because she's inside me! If I pull her out, I die!"
The pod cracked.
Steam hissed.
The girl inside began to move.
And then Queen's voice filled the room.
"You never should've come back, Yuki Aihara."