Our heroes hurtle further and further into the dark abyss. The dislodged, dangling cable car collides with a great sloped wall, leaving the occupants slightly dazed but unharmed. Geandur and Arradon, swinging from the cable itself, aren’t so lucky and slam cartoonishly into the stone wall. The hooded woman has lost her human appearance, revealing herself as a tiefling with skin the color of dried blood and a pair of small curved horns protruding from her forehead. Her hair has fallen to the side and the symbol engraved into her forehead confirms that she is the one Geandur has been searching for. As Geandur and Arradon approach their companions, the air around the tiefling shimmers for a moment and she suddenly vanishes in a cloud of necrotic smoke.
The heroes look around intently to find their foe, but all they see is panicked dwarven miners. Othfir grabs one of the cable car operators and demands that he ride back up and summon the guards, as well as Lord Frostpeak. While the cable car slowly ascends, the heroes continue scanning the ladders, minecarts, and scaffolding for the tiefling plagueomancer. The frightened miners fall silent when a smooth female voice echoes through the cavern.
The tiefling’s voice surrounds them all, nonchalantly acknowledging that the heroes caught her in the act. She is at a loss, however, not knowing the heroes or what their beef is. Geandur angrily declares revenge and brings up his home in the Southern Isles. The tiefling gives a laugh of recognition and reminisces fondly about creating the disease that she unleashed on the barbarian’s treasured island. The heroes, meanwhile, continue searching. Despite the voice’s magically-enhanced volume, the heroes know the tiefling must be close by to be able to hear them. Stalling for time, the heroes keep her talking.
They snarkily decline to answer her question about their hometowns, but she is all too glad to reveal her dastardly motives. She speaks of death and the power it holds, as well as the monumental thrill of wielding the ability to craft and manipulate such a power. She also tries to play into Geandur’s bloodlust, claiming that he too must already see that wielding death is indeed true strength. When he protests, she ominously reminds him that she wasn’t the one who killed the population of The Southern Isles, she merely spread the disease. The weight of this statement is mystifying to the heroes, but hits home for Geandur.
Meanwhile, Arradon has climbed a short ways up the tiered mine wall and Quinn has wandered into the darkness and located Arradon’s grappling hook, feared lost forever. Morningstar tries and fails to calm down the miners, while Seraphina and Othfir grow weary of the tiefling’s smug demeanor. It seems the tiefling feels the same as she bids the heroes adieu saying that she's left them a gift. As the words echo through the air, a strange mist begins to materialize and descend upon the heroes and miners.
The heroes find that the mist stings, but that it has a much worse effect on the miners. The dwarves begin to scream as their skin begins to decay and hang from their bodies. Simultaneously, a deep sound of grinding metal and stone fills the air. As the dwarves continue suffering, a massive steel trawler begins to rise into the air. Quinn acts quickly and hurls the recovered grappling hook through the air, securing it on the trawler. As Quinn climbs to the top, Geandur and Morningstar run to catch the rope before it leaves the ground.
The trawler is filled entirely with coal except for the figure of the tiefling. Quinn, having gone unnoticed, flings a dagger. The blade plants itself in the tiefling's shoulderblade and the heroes are treated to an echoing cry of pain before the voice-enhancing spell dissipates. Geandur quickly reaches the top as well, followed by Seraphina who has taken to the air on her ethereal wings.
Unfortunately the dwarven miners have entered the realm of the undead and have begun advancing on the heroes. A zombie dwarf grabs Morningstar's ankle and pulls him from the rope. As the trawler pulls the rope out of reach, the zombie beats Morningstar unconscious. Othfir drags a zombie cable car operator into one of the remaining cars. Swatting away the zombies arms, he finds the activation wand and sets the cable car into motion. Arradon fires a duo of arrows to take down the undead dwarves around Morningstar while Seraphina unleashes a barrage of magic missiles at the plagueomancer herself. No sooner do the bolts of energy hit their mark than the aasimar dives down to the fallen Morningstar, healing him just enough to bring him back to consciousness.
Geandur, filled with rage and a lust for vengeance, rockets across the expanse of coal and slams into the tiefling. The two of them tumble over the other side of the trawler, both managing to catch themselves on the side. Geandur recklessly lashes out with a hand axe, landing a blow and managing not to plummet to the ground below. Meanwhile, the zombie miners have begun climbing up the wall towards Arradon, as well as aboard Othfir's cable car. Othfir uses the undead operator as a plow and knocks most of the zombies off, but a couple remain holding on to the edge. As the dwarven barbarian dances around on rotten fingers, he shouts for Arradon to hurry up and climb on the cable car. Quick as one of his own arrow's, Arradon dashes through the throng of zombies, catching hold of the ankle of one of the miners clinging to Othfir's cable car. Between the two of them, they're able to rid the car of their undead foes.
Seraphina flies back up to aid her allies on the trawler, while Morningstar heals himself with both potion and spell. Holding out his sacred shield, he unleashes a dome of heavenly energy, filling the zombies with fear. Up on the trawler, the tiefling takes an easy arrow from Quinn before vanishing in another toxic cloud and appearing back on the trawler. Geandur climbs back aboard and positions himself with his enemy between him and Quinn. The tiefling takes another stab from Quinn before turning to Geandur. Breathing heavily and bleeding profusely, she tells him she hopes he'll think on what she said and that perhaps they'd meet again. With that she vanishes in another necrotic cloud.
The plague mistress has disappeared from view, but the telltale sound of friction reaches Seraphina's ears and she watches their foe slide down a cable towards the swarm of zombies. Othfir and Arradon spot her and with a characteristic calm and immense skill, the elf fires an arrow and the form of the tiefling drops from the cable into the mass of zombies.