They left the relay basin behind before the sun reached its highest point.
The forest continued thinning as they moved east.
Soon the terrain changed again.
Less vegetation.
More exposed stone.
Large slabs of rock stretched across the ground like broken plates from an ancient structure.
Instructor Han slowed their pace.
"The flow is stronger here."
He placed another sensing plate on the ground.
The plate reacted instantly.
Lines of light spread outward and formed a dense pattern beneath the stone surface.
Xu Liang looked at the pattern carefully.
"More channels."
Instructor Han nodded.
"Much more."
Yan Rui crouched beside the glowing lines.
"This is no longer an outer relay."
Senior Qiao looked toward the stone ridge ahead.
"What is it?"
Yan Rui pointed forward.
"A corridor."
They moved again.
The terrain soon narrowed between two massive stone walls rising naturally from the earth.
But once they stepped inside, it was clear the structure was not completely natural.
The ground beneath their feet was too smooth.
The stone walls too evenly shaped.
Instructor Han activated his sensing plate again.
This time the entire corridor lit up faintly.
Multiple formation lines ran beneath the stone floor.
All of them flowing east.
Xu Liang frowned.
"This entire passage is part of the network."
"Yes," Instructor Han said.
"And it channels pressure toward the center."
Yan Rui nodded slightly.
"This is one of the main supply routes."
Lin Xuan felt the fragment react immediately when they entered the corridor.
Stronger than before.
Each step forward increased the pulse.
Not painful.
But impossible to ignore.
Xu Liang noticed the change.
"Still reacting?"
Lin Xuan nodded.
"Yes."
"Direction?"
Lin Xuan didn't need to think.
"Straight ahead."
They walked for nearly half an hour through the stone corridor.
The deeper they went, the stronger the spiritual pressure became.
Not hostile.
Just dense.
Like the air itself carried weight.
Instructor Han finally stopped again.
"The pressure gradient is increasing rapidly."
Senior Qiao looked forward.
"How far now?"
Han studied the sensing plate carefully.
"If the flow continues like this…"
He paused.
"…less than a day."
Yan Rui smiled faintly.
"Told you."
Before anyone could respond—
Lin Xuan suddenly stopped walking.
The fragment pulsed sharply.
Different from before.
Not just reacting.
Warning.
Xu Liang noticed immediately.
"What is it?"
Lin Xuan looked toward the far end of the corridor.
"There's someone ahead."
Everyone instantly became alert.
Senior Qiao raised a hand.
"Positions."
Xu Liang moved to the front.
The masked Hollow Vein cultivator shifted silently to the side wall.
Yan Rui stood casually, but his eyes sharpened.
Instructor Han extinguished the light from the sensing plate.
Silence filled the corridor.
Then footsteps echoed faintly from the darkness ahead.
Slow.
Calm.
Deliberate.
A figure appeared at the far end of the stone passage.
Robes dark.
Aura steady.
Foundation realm.
But unlike the others they had met—
This cultivator carried a symbol on his sleeve.
A thin silver mark shaped like a spiral.
Yan Rui exhaled quietly.
"…Well."
Senior Qiao's voice turned cold.
"You know him."
Yan Rui nodded slightly.
"Yes."
Xu Liang asked the obvious question.
"Who is he?"
Yan Rui's faint smile disappeared.
"A core member of Hollow Vein."
The stranger stopped about thirty steps away.
His gaze moved across the group slowly.
Then settled on Lin Xuan.
For a moment—
No one spoke.
Then the man finally said,
"You arrived earlier than expected."
The air inside the stone corridor suddenly felt much heavier.
Because this time—
They weren't facing an observer.
They were facing someone who already knew they were coming.