The group made its way through the network of dank, steamy tunnels that served as a ventilation system for the dwarven mines deep in the mountains. Only through careful study of the tunnels’ construction and examination of the patterns of escaping steam did they manage to find their way to the Nexus: the control center for the entire ventilation network.
But they were not the first to have arrived. They hid and listened while a small convergence of Serpent Folk and Shadar-Kai stood debating the situation, discussing whether to continue into the tunnels or activate “the device.”
The intruders eventually detected the Irregulars and attacked, but they were no match for the heroes, who made quick work of them. Intrigued by the talk of a “device”, they kept one of the Serpent Folk alive—a shaman who was quick to betray his fellows. The “device”, he explained, was in a far room, and had some use related to the ventilation system. He believed that activating the device would seal the system in some way, making the Serpent Hoarde’s passage through the mountain impossible. But some of his fellows believed that activating the device would do the opposite, further opening the system so that the Hoarde could pass through unimpeded.
Augustus took charge of the prisoner and demanded that he lead them to the device. And so he did, through a room full of traps, past a room full of his allies (which the group dispatched), and into a tall, cavernous room crossed by two colossal metal pipes containing some sort of liquid. At the height of the room, they had learned, there was a control panel that operated “the device”. Around the edges of the room wound a staircase that eventually led up to the panel.
Hoards of Serpent Folk entered the room via small ducts and narrow fissures in the rocks, attacking the heroes immediately as they raced up the winding the staircase toward the distant control panel. Some of the Serpents were capable of flying, making for a distinct disadvantage to the climbers.
The snake entered when the climbers were roughly halfway to the top, so large it seemed impossible that it could come through the tiny crevasse, so long it took some time before it was in full view. It slithered to the bottom of the cavern and sought its prey, but a few well-placed and well-powered arrows from Arakos kept it slowed and weakened.
The group was approximately 50 feet from the floor of the cavernous room, with still another 30 feet to go, when a blow from a lizard man pushed Faegin to the stone floor. Insubstantial and able to roll with the impact, he survived with limited damage from the fall, but the blow itself hurt him grievously.
Soon, Saranco the monk joined him there, a leap across a corner of the chasm having gone horribly wrong. The fall did considerably more harm to Saranco than it had done to Faegin, and Faegin was able to teleport back to the stairwell, while Saranco was not.
The giant snake made its slow approach. Saranco leapt high onto the rock wall and began to climb. But he did not count on an arrow from one of the lizard folks. It struck him in the back, knocking him unconscious. The fall did the rest. And so the one called Stonefist was dead.
The others had no time to recover the body, as the room was swarming with Serpent Folk: Yuan-ti, Lizard men, and serpents of varying type and size. Kirshakru made it to the device and activated it, sending a fountain of acid from a spigot at the top of the room cascading down in all directions.
The Irregulars ran through the acid mounted a ladder that led them 40 feet higher, through a door into the pipe in the center of the room. Up they climbed, toward unknown peril.