I finally realized the reason for that strange feeling I was having.
“That’s weird. Normal smoke goes up toward the sky, not downward.”
“Isn’t that obvious?”
Seeing that I didn’t understand, Satoru said, with the attitude of an intolerable know-it-all, “They’re attacking the enemies inside the tunnels with poisonous gas that’s heavier than air.”
I gasped. “If you knew, then why didn’t you…!”
Suppressing my irritation, I continued down the tunnel, thinking over the paths we had taken so far. There was one long uphill segment that I had hoped would lead aboveground. But when we were close to the surface, it dipped downward again, as if purposefully trying to disappoint us. If we could make it there, then maybe we could avoid the poisonous gas.
Without light from the glowworms, we ran around the labyrinthine tunnels in a state of near-panic. It would be a miracle if we managed to find the right path.
“This one goes uphill!”
I felt a long incline. Although our legs burned as we ran upward, we gritted our teeth and kept going. The pain was proof that we were still alive.
Eventually, the ground flattened and started sloping gently downward.
“Let’s wait here for a bit.”
Once the nest filled with gas, all we could do was hope that it wouldn’t reach us. If the paths had been straight, it would have been a better idea to keep running, but the tunnels stretched out all around us like a web. The gas could travel around and come back to us, so in this case the best bet was to find higher ground.
We sat down in the darkness.