Folding Halls of Halas

The Folding Halls of Halas is an extra-dimensional manor with about one hundred interconnected rooms, created by the archmage Halas Lutagran in the Calamity. Halas created a special key called the Heirloom Sphere, which has ever-changing clockwork puzzles that serve as the key to entering the Halls.

The time inside of the Halls is different than on the Material Plane. Approximately one day passes in the Material Plane for each hour spent in the Halls, although the various chambers may not be consistent.

Description
The rooms in the dungeon are connected by passageways with an extraplanar essence, functioning like mini teleportation circles. A blue dragon, Thelashas, guarded one exit of the manor in exchange for food. The Halls are protected by mage hunter golems. Other dangerous creatures exist within the manor as well.

Tapestry entrance
This entrance is a stone room supported by four pillar, and on the walls parallel to each other four different colored banners (red, green, blue, and black) hang twelve feet off the ground. All the banners have the symbol of Halas in gold in the center.


 * The blue banner hides a stone dragon statue with sapphires for eyes. When the banner is moved the statue emits a blue electrical energy.
 * The green banner hides a statue of a sickly, bloated humanoid creature. When the banner is moved a green poisonous gas fills the chamber.
 * The red banner hides a red wooden door with the symbol of Halas painted on it. When the lock is picked, a magical flame bursts out and the door can be opened. This door leads to the Study.
 * The black banner presumably hides a statue linked to the "wailing creature". It is also the passageway to the Dining Room.

The link between the red door and the Study was later severed by the Mighty Nein when they destroyed the door itself in an effort to get past it.

Diamond entrance
This entrance is a diamond-shaped chamber with turquoise-colored marble and a relief sculpture on the ceiling of a curving tower encircling a humanoid figure without a face. The tower resembles U-shaped twisted tree with a series of smaller branches shooting off of it, and small gears, windows, and doorways are seen within the design. The chamber has two archways opposite each other: a gold one that leads to the Garden, and a silver one that leads to the Guest Chamber.

Study
The study is a seventy-foot tall chamber full of books, desks, and cabinets. One cabinet was actually a mimic and animated when touched. Above one of the desks is a twelve-foot tall, six-foot wide picture of Halas sitting in a chair. In the desk was a jar of glass beads, a large vial of ink, and a small porcelain doll with oddly realistic hair. One of the walls has a forty-foot tall, fifty-foot wide stained glass window up one level of ladders.

The stained glass window has a layout of the planes: the Ethereal Plane, Astral Plane, and four Elemental Planes are all pictured. There is no Divine Gate shown on the window, indicating this design may be over eight hundred years old and pre-Calamity. It has a small, red circle within the Astral Plane that is not tethered to anything. By touching the red circle, a person is transported to the Dragon Guard Exit.

When some of the party revisited the room in, it had been ransacked, presumably by Yussa Errenis. The portrait was gone, and all but three books were missing.

Dragon guard exit
This chamber is an arrow-shaped chamber with dark hallways. The chamber is filled with gold, gems, bone shards, a pedestal with an orb set into it, and a raised stone platform in the middle. The platform functions as the entrance to the chamber from The Study.

At the end of both hallways is a green-blue crystal set in an alcove which can absorb any elemental energy, but are able to activate a portal out of the Folding Halls when they are matched. Across the floor are grooves that feed the energy from the crystals to the pedestal with the portal.

In addition to the dragon that Twiggy killed on the Mighty Nein's first visit, the room was guarded by a construct which appeared from a rift when Fjord, Beau, and Yasha passed through in.

Garden
The garden is a lush tropical jungle, heavily overgrown with ferns and thick jungle trees, with a waterfall pouring down a sheer mountainside cliff into a small murky algae-covered pool. A small cave with a stone outcropping sits sixty to sixty-five feet up the cliff, leading inward to a large tunnel before shrinking to a medium pathway leading to the Tower Machine. Behind the waterfall is a small cavern with a doorway inlaid with hexagonal carvings against the back wall, which leads to the Study. The pool is thirty feet deep, and a vortex within leads into deeper darkness below. A large knot in a tree serves as an archway. It is not yet known where the pathways into the pool and tree lead.

There are multiple creatures living in the garden: scribe mites which are attracted towards magic for food, bullywugs, and a froghemoth.

Tower machine
The tower is a curving clockwork tower in the middle of a void expanse with a walkway spiraling up and down its length. Flashes of purple lightning illuminate the area, rocks of various sizes float around the structure, and assorted pieces of metal and machinery such as adamantine pistons can be seen. Along the tower is a ten- to fifteen-foot stone and metal ledge that functions as a walkway, though protruding gears block the path. There are mechanical pieces along the walkway crackling with blue energy that is whirring and spinning, though their exact purpose is uncertain

There are a few paths from the tower machine. The lowest known doorway leads to the Arcane Armory, and it sits on a floating island with purple glow.Two hundred and fifty feet above it is a doorway on the side of the tower that leads to The Garden. One hundred and fifty feet above that is a circular brown wooden doorway that glows blueish-green and leads to the golem workshop.

The Tower Machine appears to be the central structure of the Folding Halls, with the other demiplanar rooms somehow bound to the Tower.

Arcane armory
A long, wide hallway lined with pillars and lit with permanent green torches, the arcane armory has a double set of heavy metal doors that act as the only exit, opening out onto an island orbiting the Tower Machine. Halfway across the room is a fifteen-foot trapped area which triggers two arcane cannons at the end of the hall. Behind the cannons are multiple crates and several magical items.

Arcane cannons The cannons are made from a light ivory wood and have similar glowing elements to a strange machinery in Gelidon's lair. On top of the cannons are few levers, a small chair, and five buttons: deep green (acid), red (fire), light blue (frost), intense blue (lightening), and dull green (poison). When triggered, they shoot large amounts of arcane energy which is continuously fed through the floor.

Golem workshop
The workshop is a square chamber with rounded corners containing a cluttered workshop with tools for carving, chiseling, molding, and bending. There are four granite tables facing each other from an open center, and in the middle of the floor is a big stone slab with a bunch of dull carvings in it. There are large boxes containing raw and partially smoothed stone boulders resting at one of the corners, and ingots of adamantine sitting near an anvil covered in runes that sits to the right side of the chamber at the foot of a fiery blue forge. There are books with design elements scattered across the chamber, developed by Halas specifically for the construction of the Folding Halls. In front of the forge stands a metal golem, standing about twelve feet tall and made from the same material as the ingots, one arm ending in a set of hooked tongs, and the other in a hammer. The golem acts as a helper for the forge.

There are two doorways in this workshop, one to the Tower Machine and one on the other side of the room marked by a simple gray door that leads to the experiment chambers.

Experiment chamber
The experiment chamber is a dark and damp chamber that is lit with a faint flickering green light coming from glowing orbs that are affixed to portions of the wall. There are chains hanging from the ceiling, and a very faint rhythmic beating sound that can be felt as a thrum in the floor. In the center are ten nine-foot tall glass pillars set at different elevations. They are frosted from the inside by a murky liquid and have rotting corpses within. Three of them are broken. The corpses appear to be experiments of Halas to try to create the perfect clone harnessing the regenerative powers of the Permaheart.

Three doorways lead to this room: a door to the golem workshop, a dark wooden door with a polished iron frame and a cut purple gem embedded, labeled "The Sea" in old Draconic, in the center to the dreadnought, and a plain brass door to the heart study.

Heart study
The study is a trapezoidal room with grey stone walls lined with shelves of jars filled with organic matter that pulses to the rhythm of the heartbeat audible throughout the chamber. There is a large central roller desk filled scattered research notes, sketches, and small tools, and above which hangs an iron chandelier. A red carpet lies on the hardwood floor in the center of the room. Moving a lantern on the shelves activates a trapdoor beneath the carpet, which leads to the Permaheart. Another door in an alcove leads to the experiment chamber.

Permaheart
The Permaheart chamber is a dark red stone triangular room that smells of iron and shines with moisture. The only entrance to this room is through a trapdoor in the heart study.

In the center sits the Permaheart, the swollen and still-beating heart of the Laughing Hand, which sends out a nauseating pulse with each beat. The heart is suspended by its aorta within a glyph-covered, magically-reinforced glass container. The glass is smeared with viscera on the inside with pieces of flesh collected at the bottom; some bits of flesh have breached the containment, as heavy veins from the heart have rooted themselves into the stone throughout the entire chamber. There were once chains affixed to the glass, but lie loose and broken across the ground.

There are faintly glowing glyphs of symbols and equations at each corner, which weaken the glass container when broken.

Dreadnought
This "room" is actually a location within the Astral Plane, a formless sea of silvery mists speckled with pale starlike motes. The entry door is on an enormous rock island to which attached chains bind an astral dreadnought covered in spiky armored plates. A platinum plate is bolted to cover its eye, and both claws are bound to its side. Its jaw holds a twelve-foot wide mouth lined with layers of hundreds of two-foot teeth. A pair of chains at the corners of its jaw connect the sides of its mouth to two large levers to each side of the door. One of the levers appears to release all the chains, while the other causes the dreadnought to open its mouth for entry into its demiplanar donjon. A second door is located about thirty feet below the first, presumably leading to the crystal mines.

Donjon
The dreadnought's demiplanar donjon is a cavernous dark chamber, too large to see the far walls. The floor is stone, and there are distant sconces of burning torches and candelabras set in the center around a small arranged set of tables. The exit is through a Circle of Plane Shift on the ceiling, which leads to the Study.

Circlebound chamber
The circlebound chamber is a dark, charcoal-colored room. Deep red tapestries hang from the walls, depicting elements of the Blood War between devils and demons. All sorts of massive, grotesque, violent and detailed displays of carnage between the two warring factions of fiends surround the interior of the chamber. A blood-soaked table sits next to a rough-hewn stone door that holds all manner of gruesome cutting and carving tools. There is also a large empty basket equally splattered with dried gore. A few small tables and a single shelf line the edges of the room. In the center of the room is a fifteen-foot circle of dull burning purple light, holding a captive mad horned devil.

Prison of Soot
The prison is reached down a long stone staircase without walls. At the bottom is a cold, dark, circular room about sixty feet across, with dark steel walls, granite floor, and a granite ceiling holding an inactive mage hunter golem. Two low flickering torches burn at the sides. Across the room, another staircase leads down into an identical room with adamantine storage boxes to either side for items taken from inmates. Particles like dust motes float through the air and are displaced by movement, but don't seem to move with the air.

The third floor down contains ascending and descending staircases and a pair of barred prison cells to the sides, about twenty by twenty feet each which both contain assorted decomposing bodies. The fourth floor was identical, and was where Yussa Errenis was held when he was captured.

Not yet explored

 * The Bedroom
 * Dining Hall
 * Carving Farm - Where Halas grows his food.
 * Guest Chambers
 * Crystal Mines
 * Fleshmend Facility - A medical facility where Halas can tend to any wounds.
 * The Nest
 * (±75 or 75, 80% of the halls - unnamed areas)

History
Halas found a simple extra-planar chamber drifting across the planes and shackled it to the tower to study it. Within the chamber, he found a swollen beating heart locked in a magical energy field. He dispelled the energy field, only to find the heart was sending out waves of corrosive energy. Halas managed to imprison it and experimented with trying to siphon its cursed energy into a cloned human body. After sending many failures into the Astral Sea, he successfully developed a possible vessel to which he planned to transfer his soul via a Magical Jar in one of his ritual chambers within the dreadnought.

The Mighty Nein and Twiggy arrived in the tapestry entrance and realized Yasha was not with them. There were two mummified corpses which Caduceus spoke with, learning that they were killed by "the wailing creature" that came from behind the black banner. They pulled the blue and green banners aside, avoiding the green gas by sheltering within Leomund's Tiny Hut. They then pulled aside the red banner, revealing the door. They successfully picked the lock and avoided the flame. Caleb sent Frumpkin into the hallway and the party followed, arriving in the study.

There, the party inspected the portrait above one of the desks, and noticed the red circle on the stained glass window. Fjord touched it and the window loudly shattered, sucking him into a black void and causing him to vanish from the others. The window reformed and closed behind him. Beauregard and Jester ran up to the window to follow Fjord and noticed a fingerprint on the red dot. Nott and Twiggy checked The study for information, and were attacked by a mimic disguised as a cabinet. Nott finished it off with one of her "explosive" bolts. They then continued the search, and found:
 * A jar of glass beads, a large vial of ink, and a small porcelain doll with oddly realistic hair
 * A large red leather-bound book with sapphires embedded in the cover
 * A book titled: Public Debate Records: Forum of Ziedel
 * A book with a burn mark on the front where a title should be.

Before anyone could investigate further, Beau touched the red circle and disappeared with Jester. Twiggy and Caduceus followed them, leaving Caleb and Nott alone in the library. Nott and Caleb continued to look for books, getting two more before they joined the others. Arriving at the exit, Fjord found himself facing a young blue dragon, and attempted unsuccessfully to negotiate with it. When Beau and Jester came in, Beau summoned a fire elemental to attack the dragon by smashing her red elemental gem. Caduceus and Twiggy fell from the ceiling shortly thereafter.

Fjord and Beau found the two green-blue crystals down each of the hallways. Beau noticed the groove running on the floor. When Jester cast Hellish Rebuke, the cold energy shot to one of the crystals, and energy from the crystal then ran through the groove in the floor towards the center room pedestal. Fjord cast Armor of Agathys on himself to smash his head so that the other crystal could absorb the cold energy in the same way. Energy running through two grooves in the floor led to another orb in the pedestal. Beau ran to the pedestal orb, reached out, and vanished. The fight continued and when Caleb and Nott finally dropped into the chaos, they saw an angry dragon on fire, the fire elemental, and a four-foot tall Halas (Twiggy using the Disguise Self spell). One after the other, Caduceus, Fjord, Caleb, Nott and Jester ran to the sphere and vanished, leaving Twiggy alone. Twiggy then popped out of hiding and shot the dragon in the heart, killing it. She then ran to the sphere, touched it, and vanished, finding herself with the others back on the Balleater.

Entering The Folding Halls of Halas again to look for Yussa Errenis, the Mighty Nein find themselves in the diamond entrance. Beau smells earth and greenery from the gold arch and they decide to go through it towards the garden. Upon entering, Beau recognizes the scribe mites which attack magic casters. They notice a slight opening behind the waterfall, but begin to hear frogs croaking. Using her Ring of Water Walking, Nott dashes across the pool toward the waterfall and is swallowed by a giant froghemeth rising from the depths of the pool. Caleb casts Fireball, hitting the frog creature and several bullywugs. His use of magic also draws the scribe mites to lightning attack him. In the fight Caduceus also got swallowed, and Caleb cast his new spell, Widogast's Web of Fire. Jester finishes the frog creature scaring the frog-men away. The party discovers all the doorways in this room. While they search, Caleb sends Frumpkin through to The Study and discovers that the books it once held are gone.

The party rests on the top of the cliff and uses the mirror to contact Allura Vysoren. She warns them that if there's a golem workshop within the Folding Halls, there are also probably roaming golems. They hear heavy approaching footsteps as a metal golem (resembling the figure on the ceiling in the first room) approaches, and quickly dive through the archway. They find themselves standing in the tower machine.

The Mighty Nein emerge onto the spiral walkway circling of the tower machine. Fjord spots the Arcane Armory island orbiting below. They decide to head down when they hear the heavy footsteps of the golem from the doorway. Running down the spiral with the golem in pursuit, they come to gears that block the pathway entirely. Beau, Nott and Caduceus get over the gears unharmed. Caleb and Fjord get caught in the anti-magic cone from the golem and attack the golem who hit them both and affixes a silencing collar around Caleb. When they leap onto the gear, giant owl Jester, manages to catch them and deposits them on the island of the Arcane Armory. Caduceus manages to Command the golem to turn itself off, and it begins plummeting. Jester, pushes Nott off the edge, and with Feather Fall and Fjord's whip she makes it to the island, and Caleb drags her through the doorway. Jester Polymorphs into a giant eagle and transports the rest of the party to the island and through the doorway.

They enter the arcane armory through the heavy metal doors. Nott manages to get the collar off of Caleb and Nott notices the trapped floor with three piles of ash on it. Through testing, they discover how they are triggered. Jester flies Caduceus and Caleb across while Beau jumps it. When the golem enters the room, they engage in battle. Caduceus is the first to jump onto the control seat of one of the ballistae and shots it, and Nott follows. They continue to attack the golem with the ballistae and the Commands spell "off". Nott gets the How do you want to do this? with the ballista's acid. Nott unlocks two boxes they found, and Caleb identifies it as a Headband of Intellect, and a Rod of the Solitary Scout. The party takes a long rest, with Fjord standing watch all night outside the dome. When they wake, they contact Allura and she gives them updates on the war. Nott disables the mechanism of the ballistae to lengthen the reload time, and the party run unharmed out of the room trough the doorway.

Caleb, in giant eagle form, ferries the party up the tower to the door they had seen above the entrance. Through the door they enter the Golem Workshop. In the workshop Caleb finds instructions for assembling a golem servant. Over four hours they succeed in building a squat golem that bonds to Caleb and names it "Little Willi".

Trough the next door they enter a strange hallway leading to the Experiment Chamber. Nott stealths to the nearest, cracked pillar, and sees the rotting corpse within. Fjord edges along the wall and can see that each pillar contains a warped humanoid shape, resembling Halas but with cancerous growths. A shape drops from the ceiling: a hulking nine-foot-tall humanoid covered in pustules and boils, with four heads and six arms, its face bearing hair and beard reminiscent of Halas.

The party immediately attacks, after a long and terrifying fight Jester gets the How do you want to do this? with Guiding Bolt, but it heals itself back to life and knocks Caduceus unconscious. Jester gets a second How do you want to do this? with Hellish Rebuke and the party begins frantically trying to damage the creature, while Jester brings Caduceus back to consciousness. But it comes back to life again, this time severely wounding Little Willi. Jester Guiding Bolts it for her third How do you want to do this? of the battle and this time Fjord hits it with his fiery Glove of Blasting and it stays dead. After a short rest, Caleb determines that the door with the purple gem is labeled "The Sea". Caleb opens the other door with Knock and sends Frumpkin to investigate, losing contact with him as he descends the staircase within. The party follows and find themselves in the Heart Study. Caleb immediately investigates the desk, finding notes in old Zemnian, written by Halas. The party locates a trap door under the desk. Jester finds the lantern on a shelf that opens the trapdoor. They find themselves in the Permaheart with a case of reinforced glass containing the beating heart of the Laughing Hand.

Beau investigates one set of glyphs in a corner, whacking its weak point, destroying the glyph. The glass around the central heart cracks slightly. The Permaheart sends out a necrotic wave of damaging energy with each heartbeat. As the encounter proceeds, the party succeeds in whacking down the tendrils as they appear. Beau moves to the second glyph, followed by Caleb, and attempts to read the glyphs. Nott moves to the third glyph and destroys it. The party discovers that the glass can be damaged and it eventually shatters and the heart is exposed. Beau gets the final hit, with Caleb adding a Web of Fire to ensure it doesn't regenerate. They return to the Experiment Chamber and discover that every sliver of Permaheart flesh and the preserved bodies have turned black and are liquefying. Caleb takes Halas's notes. They repair Willi in the golem workshop. Jester contact Allura, who Scry on the Laughing Hand and discovers him in poor condition. The party takes a long rest. Jester learns through Communes that Yussa is in the Prison of Soot. They decide to go through the dreadnought and find themselves drifting in space with the chained dreadnought. Fjord pulls the lever opening the dreadnought's mouth while Caleb summons Frumpkin and sends him within its maw, where Caleb loses contact with him. The party agrees to enter the beast's mouth towards the Donjon.