Description
The Vault of Shumas was a few days' travel on foot from the northern end of the Rumedam Desert.
Entrance
As of 810 PD, the tall stone door to the cavern was covered in sand. Wiping away the sand revealed the whole door had a faint but detailed design of knotted snakes, except that in the middle of the design was an image of a screaming male human face, the mouth of which was an open porthole about four inches wide. Six or seven inches into the porthole was an inch-wide iron rod; pulling the rod like a handle caused a series of envenomed needles to stick into whatever was placed in the porthole, but then caused the door to lift 10 feet. Inside, the temple smelled of dry rot and burnt dust; there were very old tracks in the dust; some appeared humanoid, some appeared to be wide grooves.
The entrance to the cavern was smoothly chiseled rock, 40 feet tall and about 25 feet wide. Roughly every 20 feet, there were cracked columns or pillars, a few of which had fallen; there were clusters of stone (marble or sandstone) debris. The wall was inscribed with Abyssal text. A few hundred feet into the tunnel, it began to descend slightly, from 500 or 600 feet beneath the surface to a chamber probably 1000 feet below the surface, where a warm light was visible.
Altar chamber
This rectangular chamber (85 feet by 100 feet) was fully lit by a soft yellow glow emanating from a five-foot diameter oval stone on the ceiling. The stone was hanging over a roughly three-foot-high, somewhat circular quartz altar with two small indentations and one other indentation twice as large as the others. The altar gave off a strong sense of desecration to the Divine Sense of a paladin. Around that altar area were three triangular pillars from floor to ceiling. Two of the pillars appeared to have damaged in the takeover. Three obelisks, each about eight feet tall and four feet wide, jutted out from the base of each pillar at various angles, and they appeared to be of a different design and material than the surrounding architecture. The altar-facing side of each obelisk had a faint, square line. These obelisks each had scimitar-wielding yuan-ti (two purebloods and a malison), and the lines were the outlines of doors that could be released if the. Killing the yuan-ti caused the indentations on the altar to fill with green fluid, and when they were all filled, the altar descended 60 feet into the nesting chamber below.
Nesting chambers
The walls of this 25-foot-wide, cylindrical chamber were completely covered in Abyssal text; the light from the stone above did not reach down to this chamber.
History
The Vault of Shumas served as a religious sanctum for an ancient civilization that existed at the beginning of the Age of Arcanum. Just before the Calamity, followers of the Cloaked Serpent slaughtered the people who lived in this sanctum, occupied it, and locked themselves away from the world. They entered a long sleep, awaiting the beginning of "our epoch", guarded by an undead spirit called the Caregiver and a manticore.
In 810 PD, Arkhan the Cruel had been receiving visions from his goddess, Tiamat, the Scaled Tyrant, urging him to find a gem-studded golden wreath, a relic "locked away by a zealot's hand", but giving him limited clues to the location. After months of frustrating research, a monk of the Cobalt Soul named Duan finally gave him the information he needed. Arkhan hired four mercenaries, including Dupont Dupont, the Headmistress, and two members of the party that would be Vox Machina, Percival de Rolo and Keyleth, while the party was taking a six-month break from adventuring together. Together, the party explored the Vault. In the altar chambers, the obelisks seemed to react to attempts to touch the altar: the square insets on the obelisks dislodged with a boom and a blast of dust, and yuan-ti of different types stepped out and drew scimitars. After defeating the yuan-ti, they gained access to the nesting chambers below. There they were greeted by the Caregiver, who was an apparition of a mature, white-haired woman in sleeveless crimson robes; when she demanded to know the mortals' business, Dupont's flippant answer was met with a weakening curse, but Arkhan used his power to Control Undead to force her to follow his commands. She called down a manticore wearing the Wreath of the Prism as a collar, and by her command it was not hostile. Arkhan donned the wreath around his own neck and immediately took damage but also gained the benefit of darkvision as his eyes changed in appearance. The party flew out of the Vault of Shumas on the manticore's back, with the Caregiver following.
