The black ate the edges. The lantern made a small island. We kept it low. I put my left hand on the wall and counted tiles under my right boot. "Two, four, six," I said, low enough to keep breath from bouncing. Lyra marked a dot every ten. Gareth dragged his toe where the floor lip shifted. Pelham kept the rope coil high and the knot ready. Rooke listened for hums and shook his head when there weren't any.
First junction: a T where the left breathed cool and the right smelled stale. The echo on the left came back wrong—too fast. I set the bone sapper on the floor. It tapped light, moved two steps, tapped again. Two beats short. Dead end at short left.
"No lamp talk," Lyra reminded me.
"Right," I said. We took it.
A shallow slope pulled us forward. I set my heel and let Anchor Step earn its keep. "Low knees," I said. The slope flattened. We paused. I drew a small line on the map. "Angle here," I said. Lyra penciled a note without looking down.
