When or how this fight slides from “evenly-matched” into “poorly-waged”, to “uneven”, and then finally into a “disaster” for the Heroes, is unclear. The Dwarven Defenders and Paladin at first make a positive impact, cutting into the Duergar line. But these Dwarf allies, battered by their opposition and not well supported by the Heroes, falter. Half the Defenders drop. Those that remain are double-teamed.
Lester’s Dire Wolves are slain. Lester himself is hit with a powerful Moon Bolt, dealing 12 points of Strength damage and effectively paralyzing the Halfling Conjurer where he stands, or, rather, where he stood before he slumped. Both the Dread Pirate Wobberts and Genive are targeted with an old favorite, the Mark of Doom. Wobberts and Kartug Igmutin are hit by Blood to Water spells, dealing them Constitution damage.
The Duergar Commander has made an appearance, and charges in. He is extremely tough and very skilled, and will slay the Dwarf Paladin almost without a second thought. Kartug Igmutin, afflicted with his Greater Curse, remains inert while the allied side begins to lose badly.
Lester is forced to Teleport away, back to the safety of the 5th Underground Storage Room that had been set up as a temporary headquarters. This location is well enough known from memory that the Conjurer can make the jump relatively safely.
Genive continues to fire arrows at any targets in sight. Wobberts is dropped to –4 hit points right before the Duergar Commander reaches him. Around this time, the spirits guiding both Wobberts and Kartug are compelled to bow out for the evening.
The even fight is rapidly becoming a rout. All of the ally Dwarves are now dead; Jaques and Genive are low on spells or worthy attacks to throw at the one remaining Cleric, the Duergar Commander, two Rogues and four Fighters.
Then the fight gets a LOT worse.
More accurately, the fight gets a LOT worse for the Duergar. There appears a bright shock of light at the far end of the Tavern, as a group bursts through the far doors, torches wiping away darkness. It is Captain Ironhaul, a Paladin, and ten Dwarven Defenders, charging to the rescue.
While the Duergar hate the Party, they still hate Dwarves worse. So forgetting for the moment the simple joy of coup de grace-ing Wobberts, slaying Kartug and advancing at leisure to easily murder the Spymaster and then Jaques, the surviving Duergar turn and rush at the incoming Dwarves.
Then Jaques casts a spell. At first it seems like an exceptionally brilliant tactical move; to raise a Wall of Fire, converted to Acid, behind the Duergar as they charge toward the Dwarves. This would have caught the Duergar between a superior Dwarf rescue force, and a Wall of Acid issuing forth waves of acid damage on Jaques’s turn, out to a distance of twenty feet. Effectively it would be the anvil upon which the hammer of Ironhaul’s support force would flatten the Duergar and win the day.
Instead, Jaques changes his mind and decides to cast the Wall of Acid BETWEEN the Duergar and the advancing Dwarves, pulsing its acid wave back towards the Duergar. So the spell then had the effect of not only halting Ironhaul and his reinforcements on one side of the Wall of Acid where all but one unlucky Duergar Rogue was not; but it also forced the Duergar to stop, turn back, and refocus their attention on a Party that was not going to get two lucky breaks in one night.
With Wobberts down and bleeding out, and Genive forced to retreat through two layers of Blade Barrier (without harm, at least), that left often-passive Kartug alone against the Duergar Commander and his retainers. Kartug had done well to be as active as he had been, subletting his percentile-dice rolling to a fellow player who normally directs Genive’s actions. But that his player had left for the night was not to suggest that he as a character has magically disappeared from the scene.
As a mercy, the Duergar Commander turned out to have only dealt enough damage to drop the half-Orc to a stable –1 hit points. Despite their better judgement, Ironhaul and his Paladin and Defenders sprint through the Wall of Acid and converge on the Commander before the Commander can finish off those Heroes lying near-death.
The last Act of this fight sees Ironhaul and the Duergar Commander hack it out in a fight to the death, with the Duergar leader slain and the Dwarf Captain badly wounded, but alive.