Upon hearing the name Trier Cave Association and their invitation to "Rat" Christo, Lumian didn't feel puzzled initially. Instead, he recalled the secret map of Underground Trier he had once seen from Gardner Martin.
The upper section of the map was as detailed as if one had infiltrated the municipal department and copied the original information.
Now, Lumian suspected that it might have been leaked from the Trier Cave Association.
This seemingly civilian organization had a large number of cave researchers. Some of them were employees of the municipal department or expert consultants. They had ample opportunities to come into contact with confidential exploration and construction information. There was no lack of people who had participated in the municipal modification decades ago. They were hands-on witnesses who had bored through various tunnels and reinforced all the quarry caves.
They had a deep understanding of Underground Trier.
