The Thieves guild dropped off some supplies in the morning for our adventurers. The bunch head out to Aster's bookshop to ask about his mercury treatise. Mercury is adaptive. It flows, it moves. Mercury might be able to contain Sheol because it is not always in the same place at the same time. It is also desperately poisonous.
While we interact with Aster, BD, Avis, and Rasmus found a trap in the basement leading to the tunnels. Eventually, the party convinces Aster to let us hed back to the tunnels through the secret basement door. We also learn that Aster has been alive for a few millennia and knows Ryfen.
In the tunnels, we mapped an access to the Moon Quarters. We also located a dozen abberations, one undead, two dragons (probably ours), and a fiend. On the way, we passed an old aqueduct, a sinkhole that used to be the Clements' house, a family of apothecaries.
In it, we found a few items, including 3 mercury vials, 18 silver coins, and a healing potion. We also found a Marcus. He was pleased to see us so we started chit-chatting peacefully... He escapes in the tunnel, fairly injured.