A metallic door lies ahead; the first they'd encountered since Catherine had entered the underground sewer.
They were now in a junction within the sewer system. Seven or eight connecting pipelines from various directions converged here into a secondary main pipeline leading to the distance. On a pathway next to the junction, there was a metal door slightly above the ground. It was a silvery door made from goblin alloy. Despite its exposure to the environment for tens of thousands of years, only the surface had a layer of rust, the rest remained intact. This was proof of the advanced metal refining technology of the Goblin Era.
