---
U-01 Shade drifted silently through the thermocline layers of Sector Theta-3.
Below her, trenches plunged into darkness. Above, the light blue haze of the upper sea shimmered faintly through hundreds of meters of pressure-weighted water. Every ping of her sonar was a whisper. Every decision made by her AI helmsman was guided by efficiency and the art of remaining unseen.
Onboard, Lieutenant Mara Kwon adjusted the periscope sensors from her console. Though the Type-212A was fully AI-controllable, Reeve had insisted on placing a human liaison aboard. It was not out of distrust—but instinct.
Sometimes you needed someone to ask: What doesn't belong here?
---
> MISSION OBJECTIVE: Deep Recon of Site Mu-9 Target: Identify unnatural seabed anomalies
Status: Underwater Structures Detected Threat Level: Unknown
---
Fort Sentinel's main CIC buzzed as the live sonar feed painted a strange silhouette.
Keira frowned at the topographic overlay. "This isn't a wreck."
"No," Reeve agreed. "It's a dome."
The outline rising from the seabed was smooth. Geometric. Too precise to be natural, and too intact to be a ruined ship. U-01 crept closer, dropping to 390 meters, her magnetic resonance sensors now picking up faint EM pulses.
A structure.
And it was alive.
---
> STRUCTURE CLASS: Submerged Facility
Designation: "Echo Spire"
Status: Power Source Minimal, Automated Systems Dormant Language Markings: Unknown (Pre-Collapse Tech)
Access Point: Sealed
Radiation: Low
---
Kwon's voice came over the secure channel. "Sir, it's built into the rock shelf. And it's humming—barely. Like something's waiting to boot up."
"Deploy a Stingray drone," Reeve ordered. "Let's take a closer look."
The small torpedo-shaped recon drone exited from Shade's dorsal tube and glided toward the dome.
It lit up the area with soft blue strobes.
What it found stopped them all.
---
Carved into the exterior ring of the dome was a symbol—a black triangle intersected by a helix and a shattered crown.
Keira's eyes widened. "Blackcrown?"
"No," Reeve said slowly. "Something older."
The Stingray drone found an access panel with a mechanical iris, locked shut by a pressure clamp and a biometric scanner. The panel bore serial code:
> ECHO-PRIME-ALPHA | Vault 01 | Keynode RED-ZERO
---
"Pull the drone back," Reeve said sharply. "We log it, tag it, and back away. Not until HQ10 are we even thinking of accessing sealed structures."
Keira frowned. "You think it's a vault?"
"I think it's worse. A bunker for something too important—or dangerous—to be left in the open."
---
U-01 banked gently and began its return path northward. It would take seven hours to reach Sentinel's secure dock.
Meanwhile, Reeve stood before the war council table.
Around it: Keira. Logistics Chief Omar Baqir. R&D head Anya Takeda. AI Control Node Projector.
"We have a new problem," Reeve said, bringing up the Echo Spire scans. "Not just rival fleets. Not just pirates. There are things in this world that predate us. Pre-collapse facilities. Sealed nodes. And maybe vaults filled with tech none of us are ready for."
"What's your move?" Baqir asked.
Reeve tapped the panel.
> NEW OBJECTIVE QUEUED:
Upgrade HQ to Level 10
Construct Deep Dock Facility (Submarine Retrofit + Mini-Sub Production)
Research Ancient Power Nodes (Requires Energy Division)
Field Test AUV Recovery Team (Post-HQ10)
"We get stronger," Reeve said. "And when we're ready… we come back."
---
Later that night, under the quiet hum of the CIC, Keira approached him.
"That symbol," she said. "I saw it before. On a crate during our salvage op. Black paint. Faded."
"You sure?"
"Positive."
Reeve stared out the observation window, eyes on the horizon.
"Then it's not just deep. It's everywhere. We just haven't been paying attention."
He turned back to his screen and began drafting a new construction protocol.
He needed a stronger fleet. More submarines. And power to reach deeper than anyone else.
Because Echo Spire wasn't waiting for discovery.
It was waiting to wake up.
---
[End of Chapter Twenty-Two]