Everyone rests overnight and in the morning John, Bane, Helmholtz and Ivelios head to the docks to try and get passage home. However, they are stopped by soldiers and escorted to the High Hall, the castle of the High Observer. He explains that he heard of their daring retrieval of the Staff and thought they would be well-suited to help him with a problem in the city in exchange. He offers pardons for their previous misdemeanours in exchange for this help, and they agree. Their task is to clear out the dungeon under an old barracks that has become home to a number of unpleasant creatures.
A short way into the dungeon, the group come across two giant bats and three swarms of tiny bats. They scramble down a sharp drop and engage in combat.
John branches out by throwing an axe at the bats. Bane attacks some of the bats with acid and poison, then hits them all with a thunderwave. Helmholtz swings his hammer about and Ivelios shoots off several crossbow bolts while protecting himself from weapon attacks, then flicks a bat on the nose and frightens one of the swarms.
At this point, a Gelatinous Cube awoken by Bane's thunderwave joins the fight. It tries to engulf Bane, who manages to escape, though the effort it takes him causes him to randomly levitate later on. John kills one of the bat swarms and Ivelios casts Witch Bolt at the Cube, which them tries to engulf him but fails. Bane hits it with several times with Magic Missile and Ivelios keeps up the Witch Bolt. Helmholtz is engulfed but Bane rescues him at the cost of a lot of damage, while John hits it with his axe. Then the cube turns on Ivelios again, who is engulfed but manages to sustain the Witch Bolt from inside the Cube until he falls unconscious. Meanwhile Helmholtz attacks it and Bane manages to pull Ivelios out of the Cube with Edwina's old staff, then stabilises him. John finally manages to kill the Cube and Helmholtz hammers the remaining swarm of bats.