The dark did not come all at once. It moved in pieces, cutting off lanes and narrowing their choices. Elias looked up and finally saw the pattern. The still-lit path led straight ahead between old power veins wrapped in dead insulation and a row of low service posts that would bottleneck anyone running through.

“A herd line,” he said.

Mara grabbed the satchel and shoved it back at him. “Now you see it.”

Something moved behind the trunks on the dead side. Not a direct rush. Just shapes crossing gaps, keeping pace. Tapping again, closer, and a whisper of feet in wet channels. The false intake call sounded once more, then stopped mid-note, as if someone had put a hand over a speaker.

“Left?” Elias said.

Mara listened a beat longer, then said, “Blocked.”

Elias turned toward the other branch. “Right?”

Mara answered without hesitation. “Drop trench.”

Elias glanced down the narrowing passage. “Forward is the choke point.”

“Exactly.” Mara pushed Lina ahead of her. “Move before they close the back.”

They ran. Elias could not do it cleanly. Every stride jarred his side. His left leg nearly folded on the first uneven grate, and only the forward drag of momentum kept him upright. The wrapped palm slipped on the satchel strap. His breath came rough and shallow. Ahead, the lit lane narrowed between trunk supports and cable bundles where old fuel lines once fed heating burners for winter air cycles.

He smelled it then. Faint. Oily, bitter, long soaked into the conduit walls. Not fresh gas exactly, but residue in a cracked line, enough that the air tasted wrong near the floor.

Mara saw him looking. “Don’t.”