The moment the screen went black, Eren knew the tower had changed.
Not the outside world. Not yet. The tower itself.
The air in the top relay room felt tighter now, as if the walls were holding their breath. The blue light from Aster hovered near the floor, the Sentinel stood by the door in complete silence, and Lira kept staring at the dead screen like she wanted to punch it for giving them the truth too late. Eren did not move for several seconds. The warning message from the recording still echoed in his head.
Run to the archive vault before the lower signal reaches full strength.
That was the one line that mattered now.
He turned slowly and looked at the screen again. The old system display had already shifted. The sky seam was still there on the larger map, the hidden station in the clouds still pulsing softly, and the lower signal line underneath the tower was rising with frightening speed.
LOWER SIGNAL: 71%
UPPER RELAY: 48%
ARCHIVE STABILITY: FALLING
Eren's jaw tightened. "It is going up too fast."
Lira stepped beside him. "Then we do not waste time."
Aster's light brightened a little. "Correct."
The Sentinel remained still, but its chest light pulsed once.
"Vault route active," it said.
Eren looked at it sharply. "You know where it is?"
The machine tilted its head. "Archive Vault is beneath the observatory. Access route was sealed after the last cycle."
Lira frowned. "The last cycle?"
The Sentinel's voice stayed calm, almost too calm. "Repeat event. Signal wake. Lower response. Upper opening. Archive stress."
Eren heard the words and felt a cold line run down his spine. This was not the first time this had happened. The observatory had seen cycles. The Archive had seen cycles. The dead world had gone through this before, and something had been buried so deep that it still remembered how to wake.
He looked at the black screen again. "If the vault is beneath us, why did the recording tell us to run there?"
Aster answered first. "Because it may contain the last stable records."
Lira crossed her arms. "Or the next warning."
"Or both," Eren said.
No one argued with that.
He turned from the screen and looked at the room itself. The top relay interface room was still humming softly, but the sound now had a rough edge to it. The tower did not feel as stable as before. Every few seconds, a small vibration passed through the floor. The signal lights on the walls kept flickering in short bursts. Something below was affecting everything above.
Eren stepped to the main console again and reopened the route map.
The Archive vault path appeared in blue.
It did not lead back through the observatory stairs. It led down through a hidden hatch behind the relay node in the floor.
He looked at it and frowned. "There is a secret hatch here."
The Sentinel stepped closer. "Yes."
"You knew?"
"Yes."
Eren stared at it for one second longer than necessary. "You really enjoy short answers."
The machine paused. "Efficiency is useful."
That almost made Lira laugh, but she stopped herself and shook her head. "Open it."
Eren checked the floor panel near the relay node. There was a thin seam around a circular plate, nearly hidden under the dust and the cables. He crouched and ran the scanner over it.
[Vault access hatch detected]
[Lock: active]
[Archive authority required]
[Candidate signature accepted]
Eren looked up. "Accepted?"
Aster hovered closer. "Your mark is enough."
He placed his palm over the edge of the hatch.
The Archive sigil on his wrist lit softly.
Blue lines spread through the seam in the floor. One lock clicked. Then another. Then the circular plate opened inward with a deep mechanical hum. Cold air rose from below. Not the surface wind. Not the tower air. This air was older, still, and heavy with the smell of dust and sealed metal.
A ladder appeared beneath the hatch.
Lira peered down. "That is a long way."
Eren looked over the edge. The ladder dropped into darkness for maybe ten meters, then ended at a narrow lower walkway lit by a thin blue strip. He could not see beyond that easily, but the route map in his vision showed a straight line into the vault corridor.
He looked at the others. "We go together."
Lira nodded. "Obviously."
The Sentinel stepped toward the hatch. "I will accompany candidate."
Eren gave it a brief look. "You are coming too?"
"Yes."
"Good."
He did not know why, but he was glad. The machine was strange and unreadable, but it had protected him on the roof. That meant something.
He climbed down first.
The ladder was cold under his hands. The deeper he went, the colder the air became. Aster floated above him, sending enough light to show the metal walls and the lower platform. Lira followed behind, and the Sentinel came last, moving with a smooth quietness that made no sound on the metal rungs. When Eren reached the bottom, he stepped onto the lower walkway and looked around.
The place was not a normal basement.
It was a hidden core corridor built beneath the observatory, sealed from the rest of the tower like a private lung. Thick walls ran both sides. Pipes and old signal tubes crossed above. The floor was lined with maintenance panels and a narrow blue strip of light that showed the path ahead. It felt less like a hallway and more like a vein running under the tower.
The route map in his vision widened.
[Archive Vault corridor detected]
[Signal interference: high]
[Lower signal proximity increasing]
Eren's mouth tightened. "It is close."
Aster's blue glow sharpened. "Yes."
Lira stepped beside him and looked down the corridor. "I do not like this."
Eren gave her a side glance. "You have said that a lot today."
"That is because today has been awful."
He could not argue with that either.
The corridor ahead had three branches. One was blocked by collapsed steel supports. Another led to a control chamber marked with old red warning lines. The third was the main vault route, a straight path with a heavy door at the end. The map in Eren's vision pointed at the main route, but the control chamber caught his attention.
It was marked with a blinking note.
MEMORY NODE POSSIBLE
He stopped and pointed. "That room."
Aster's voice came softly. "High probability of stored records."
Lira looked at him, then at the room. "Then we should take it."
The Sentinel moved slightly to the side. "Vault priority still active."
Eren nodded. "We check the memory node first. If the lower signal is rising fast, we need every clue we can get."
No one disagreed.
They moved into the control chamber.
The room was wide and low, filled with old relay cabinets, thin hanging cables, and a central terminal covered in frost. A few screens on the wall still held power, but only weakly. The air here felt different from the corridor. More charged. Eren could feel a faint pressure in his ears as he stepped in, like the room was full of something not fully dead.
He scanned the terminal.
[Memory node present]
[Data layer: deep archive]
[Access: candidate only]
[Warning: unstable record]
Eren looked at it. "That sounds bad."
"Everything here sounds bad," Lira said.
He touched the terminal.
A blue pulse spread across the screen.
The room blurred.
Eren blinked once and found himself looking at another version of the same chamber. Not the present one. The past. It was still the same room, but alive. People moved through it in a hurry. Men and women in coats, some carrying data cases, some shouting into headsets. The screens were bright. The cables were active. The whole chamber buzzed with panic.
Then he saw Doctor Vale.
She stood near the central terminal, face tired, hair pulled back, hands moving fast over the console. Beside her stood another man in a dark coat. He was speaking too quickly for Eren to catch at first. Then the recording sharpened.
"Vault stability is failing," the man said. "If the lower core finishes opening, we lose this layer."
Doctor Vale did not look away from the screen. "Then we seal it again."
"You know that is not enough."
"Yes," she snapped. "That is why I called the candidate route."
Eren felt his chest tighten.
Candidate route.
The man leaned closer. "The boy is not ready."
Doctor Vale's hands stopped for one short second. Then she said, "He will be. He has to be."
The memory shifted. Eren saw a different angle, a lower one. A child's height. He was standing there in the room, watching them. Or perhaps not seeing everything clearly. But he saw Doctor Vale turn toward him with a face that was calm in the way adults look when they are trying not to scare a child.
"Remember this," she said in the memory. "If the sky opens, the vault must stay shut until the mark wakes."
The vision cracked.
Then another scene flashed.
A shadow moving under the floor.
The room shaking.
The man in the dark coat shouting, "It is already listening!"
The terminal flashing red.
Then Doctor Vale's voice again, softer this time and full of fear.
"If the lower thing reaches the vault, the archive will not survive another cycle."
The memory broke apart.
Eren sucked in a breath and found himself back in the present chamber, one hand still on the terminal. The cold wall was under his fingers. Lira was staring at him with concern. Aster hovered close, its blue light steady. The Sentinel stood near the door like a silent guard.
Eren took a slow breath.
"Doctor Vale knew this would happen," he said quietly.
Lira looked at him. "Yes."
"She said the vault must stay shut."
"Also yes."
He turned to her. "Then why are we opening it?"
"Because she also left the route," Lira said. "That means something inside is still important."
Eren looked down at the black screen again. The memory had shown him too much and not enough. The vault was not just a storage room. It was part of the seal. A place holding something old and dangerous. Or perhaps holding the truth. He did not know yet which mattered more.
The room suddenly shook.
Not hard. Enough to make the lights flicker.
Aster's light flared. "Lower signal surge."
The Sentinel turned its head sharply toward the corridor. "Movement detected."
Eren looked up. "What kind of movement?"
The machine answered in one word.
"Hostile."
The control chamber door slammed once from the outside.
Then again.
Something struck it from the other side with enough force to make the frame ring. Lira stepped back and raised her blade. Eren grabbed his rod. The terminal on the wall flashed red. The room lights blinked twice. Then the door hit again, harder this time, and one of the outer bolts bent inward.
The voice from the recording was still in his head.
If the lower thing reaches the vault, the archive will not survive another cycle.
Eren moved fast. "Back to the vault route."
The Sentinel stepped in front of the door. "Proceed."
A third удар hit the chamber entrance and made the wall shake.
Whatever was outside was not small.
They ran.
The corridor back to the main route was only a few steps away, but the sound behind them got louder with every second. Metal screamed against metal. The control room door began to buckle. Lira was first through the corridor, Eren right behind her, with the Sentinel taking up the rear. The roof tower above them trembled again. The lower signal was affecting everything now. The hallway lights flickered in a broken line. One panel burst with sparks overhead.
They reached the vault door.
It was huge.
Thick. Circular. Reinforced with a central wheel lock and three side clasps. Blue lines ran in a ring around the frame. Old text was carved above it.
ARCHIVE VAULT
RECORD STORAGE / SEAL LOCK / AUTHORITY ONLY
Eren stared at it.
This was it.
The place the signal had led them to. The place Doctor Vale had warned about. The place hidden beneath the observatory like the heart beneath the ribs.
He stepped forward and placed his hand on the wheel lock.
The Archive mark on his wrist glowed.
The system display flashed.
[Vault authority detected]
[Candidate access stable]
[Warning: lower signal nearby]
[Proceed?]
Eren looked back once.
Lira was breathing hard. The Sentinel stood ready. The corridor behind them was now shaking more strongly, and the sound of the thing inside the tower was getting closer.
He looked at the door again.
"Open it," he said.
The wheel turned with a deep metallic groan.
The clasps released one by one. Cold air poured out from the vault seam. It was colder than any room he had entered so far. Not because of weather. Because of time. The kind of cold a sealed place holds after sitting untouched for too long.
The door swung inward.
Eren stepped inside first.
The vault room was vast.
He had expected a small storage chamber. Instead he walked into a wide circular hall lined with tall archive stacks, stacked data columns, hanging memory tubes, and wall panels covered in thousands of thin blue lines. In the center of the room stood a round platform with a control pillar rising from it. The ceiling above was high and dim, crossed by thick cable lines and inactive rail tracks. Along the walls, old archive units stood in rows like sleeping coffins.
The room was beautiful in a strange way.
And wrong in an even stranger way.
Because every archive unit in the room was still powered.
Not fully. But enough to glow.
Eren stood still and looked around.
There were so many records here that his thoughts almost stopped.
Lira came in behind him and froze too. "This… this is the vault?"
Aster hovered in beside them. "Yes."
The Sentinel stepped inside last and shut the door behind them with a heavy sound. The outside world vanished at once. Silence wrapped around the vault like a blanket.
Eren looked at the archive stacks.
Then he saw it.
A single column in the center wall was blinking with a red indicator.
Not blue.
Red.
His pulse quickened. "What is that?"
Aster turned toward it. "Priority memory core."
Lira frowned. "Why is it red?"
The Sentinel answered first. "Because it is unstable."
Eren looked at the red column. Something about it felt different from the others. The Archive lines around it were denser, stronger, and older. The system in his vision changed again.
[Priority node detected]
[Memory core: partial lock]
[Candidate connection possible]
[Warning: unsealing may trigger reaction]
Eren read the warning and let out a slow breath. "Of course it may trigger something."
Lira moved beside him, looking toward the red core. "Doctor Vale left this here for a reason."
"Everything here was left for a reason."
Aster projected a thin blue line over the floor.
[Core approach route available]
Eren followed the line with his eyes. It led to the center platform. He stepped forward slowly, every sense alert. The vault room was quiet, but not empty. He could feel it. Something in the archives was awake enough to notice him. The deeper he walked, the more the sigil on his wrist pulsed in response.
Then the red core spoke.
Not with a voice.
With a memory.
A pulse of light jumped from the column and spread through the room in a thin wave. Eren froze as the image formed in front of him. Not a full vision this time. Only a fragment. But it was enough.
Doctor Vale.
She was standing in this same vault room.
But she was not alone.
Beside her stood Eren.
Older than in the photo. Older than the boy in the relay memory. He looked almost the same as he did now, but not quite. There was focus in his face. Tiredness. A readiness he did not have yet.
His heart stopped for one beat.
The image was brief. But it was real enough to shake him.
"What…" he whispered.
Lira turned to him. "Eren?"
He stared at the red core, breathing a little too fast now. "I was here."
The vault memory flickered again.
Doctor Vale's voice came through, broken but clear.
"If you wake before the full seal is broken, then we still have a chance."
The image of his older self faded.
Lira stared at him in silence. "You remember something?"
Eren did not answer at first.
Because he was looking at the red core and understanding something he had not understood before. The Archive had not only recorded his name. It had recorded him here. At some point in the past. Or perhaps in a broken version of the past. That meant this place did not just know him. It had tied him to itself in a way deeper than he expected.
Aster's voice was very low.
"This is significant."
The room shook.
Everyone turned toward the far side of the vault.
The archive stacks on the opposite wall trembled slightly. One of the hanging memory tubes swayed. A deep sound echoed through the floor below them. Not the roof. Not the corridor. Below the vault.
The lower signal.
It was close.
The Sentinel moved immediately. "Reaction beginning."
Eren looked toward the center core, then toward the floor, then back to the door. The vault had given him the first clear proof that he had been here before. It had also brought the lower signal closer. The two things were tied together more tightly than he wanted.
Aster's blue glow flashed. "Memory core may hold route data."
Eren took one step toward the red column.
Then another.
The system prompt appeared again.
[Priority core interface open]
[Access memory?]
[Or seal core immediately?]
He stared at the prompt.
This was the choice.
Open the core and learn something important, or seal it and protect the vault from whatever might wake in response.
The floor shook again. More strongly this time.
Lira looked at him. "You have to decide now."
The Sentinel turned toward the door. "Hostile force approaching."
Eren could hear it too now. A huge sound outside the vault door. Metal striking metal. Something dragging itself forward. Something trying to reach them.
He looked at the red core. Then at Lira. Then at Aster. Then at the Sentinel.
His breath steadied.
"Open it," he said.
Lira's eyes widened a little, but she did not stop him. Aster's light sharpened. The Sentinel took one step back from the center and turned its head toward the vault door, ready for trouble.
Eren placed his hand on the red core.
The room lit up.
Blue lines spread from the center of the vault in all directions, racing across the archive stacks, the wall panels, and the hanging tubes. The red core cracked open like a shell revealing the memory layer inside. A burst of light filled the vault. Eren's wrist sigil burned bright enough to make his vision blur.
Then he saw it.
Not the room.
A memory.
A clean white hallway.
Doctor Vale running.
The Archive alarms screaming.
The sky above the observatory opening.
And a voice, not hers, saying one terrible sentence.
"Seal the vault. The lower thing has learned his name."
Eren's eyes widened.
Before he could react, the memory cut out.
The room dropped back into darkness.
And the vault door behind them began to shake so hard that the entire floor trembled.
Whatever had been chasing the lower signal had found them.