Thakorsil's Seat

Thakorsil's Seat was a powerful minor artifact that had the power to completely bind and enslave those who sat upon it. Constructed in the ancient kingdom of Yhalvia in Narfell to yoke a devil lord, it found its way into the possession of Larloch, the Shadow King of Warlock's Crypt. He gave it to Szass Tam, Zulkir of Necromancy, for his plot to control the demon lord Eltab and take over Thay. However, use of the dread Seat had a terrible cost: it required mages of good heart to be sacrificed and destroyed body and soul in the ritual of twin burnings. Their essence fueled the creation of the runes of chaos and a nine-sided crystalline pyramid, which progressively eroded, bound the occupant of the Seat to the will of its owner. Operated by such rites, Thakorsil's Seat was a device of great evil and corrupting influence.

Description
Thakorsil's Seat was a massive and elaborate throne carved of dark veined stone. It had a keyhole-carved back, its arms were in the form of the neck and head of snarling dragons and each foot was a draconic claw clutching a sphere.

Powers
Thakorsil's Seat had several limitations and the ritual of twin burnings was long and complex with very specific conditions, which made the Seat very difficult to use and gain its great power.

The chair immediately attacked all who sat in it with continual and overwhelming mental domination and physical binding. If the victim had been forced or tricked, then they had a chance to resist when the ritual of twin burnings was performed. If they had sat willingly or been magically compelled, such as by a separate domination effect, then they had no chance of shaking off the chair's effects. Only those with an innate magical resistance could try to resist in such circumstances. In any case, if they failed, then they were magically bound, trapped in the throne and unable to move. All they could do was talk and think.

At that point, the owner of the Seat had to perform the ritual of twin burnings to create a crystal pane inscribed with a rune of chaos around the Seat, so that the prisoner would remain and trapped and bound. The ritual involved the sacrifice of a good human mage of a certain level of power dependent on the number of runes of chaos inscribed. This act was utterly evil, completely destroying the victim in body and soul. It took a full night and day to perform, it could only be performed during the full moon, and only once a month. During the ritual, the runes already on the Seat played deep and eerie musical chords. Finally, the ritual of twin burnings had to be successfully performed nine times to assemble a nine-sided crystalline pyramid around the Seat, with each face bearing a rune of chaos. With every rune created, the victim's will to resist grew steadily weaker.

With at least one rune of chaos in place, the victim could not leave the Seat by any means, but someone outside could shatter the crystal panes and free them. A broken pane would necessitate the ritual of twin burnings to be performed once more. If all were destroyed, then the victim was freed from the bonds of Thakorsil's Seat.

However, if all nine runes of chaos were created and the crystalline pyramid around throne was completed, then the soul of the occupant was permanently bound to Thakorsil's Seat and fully enslaved to its owner. They had no more will to resist. The bound creature could then physical leave the seat, and even pass through the crystalline pyramid, but remained under the will of the chair's owner. At this point, the enslaved creature could only be liberated by multiple wish spells, direct intervention by deities, or the destruction of Thakorsil's Seat (itself an equally massive undertaking), or an action of similar magnitude.

Furthermore, while the Seat was active, it radiated magical interference that dampened all divinations spells and effects with a radius of 200 miles (322 kilometers)  Greater Divinations were reduced in efficacy over much of the area, and blocked entirely in the immediate vicinity of the Seat. Spells such as clairaudience/clairvoyance, ESP, and even detect evil, and magical items that had similar magic, like crystal balls and amulets of ESP, became completely useless. This apparently inadvertent side-effect worked to conceal the chair's owner's wicked activities from the outside world. Thus the creature occupying the Seat could not be located by any power or ritual cast by all but the most absolutely powerful casters.

History
Thakorsil's Seat had its creation in Yhalvia, an ancient kingdom that was part of the empire of Narfell (−946 DR to −150 DR). Yhalvia was ruled by the devil lord Orlex, but a band of rebellious wizards arose to depose him. Led by the archmage Thakorsil, they created the throne known as Thakorsil's Seat to imprison and permanently bind and enslave the evil fiend. Unfortunately, although they had the best of intentions, the device demanded deeds of despicable evil to function. Thus, they devised the ritual of twin burnings, which involved the sacrifice of beings of good heart, believing this was for the greater good, that the ends justified the means.

They went ahead with the horrific rites, and successfully bound and enslaved Orlex in the Seat, forming a council of wizards that governed Yhalvia. However, corrupted by the sacrifices and with Orlex as their slave, they soon became as cruel, depraved, and wicked as the devil they had replaced. In time, others overthrew them, Orlex was banished to the planes and Thakorsil's Seat was lost and believed destroyed.

At some point, Thakorsil's Seat—and presumably the details of the ritual of twin burnings too—came into the possession of Larloch, the Shadow King of Warlock's Crypt, who never actually made use of it.

Szass Tam, the Zulkir of Necromancy of Thay, visited Warlock's Crypt around 1366 DR. What transpired was unknown to the outside world; the two came to some deal or alliance, the details of which were again unknown to outsiders. Larloch gave Szass Thakorsil's Seat and several other powerful magic items and artifacts, including the Death Moon Orb, and a number of hooded companions, to aid him in his plots to control Thay and the demon Eltab.

Szass Tam then embarked on his scheme to bind the demon lord Eltab. Centuries before, Eltab had aided the Thayans in shaking off Mulhorandi rule, but was subsequently imprisoned beneath the capital, Eltabbar. Szass Tam had realized that the demon lord would soon break free, and decided to instead hasten his escape and then fully enslave the fiend. In the Year of the Shield, 1367 DR, Szass Tam used the Orb's power to first free Eltab—which triggered a major earthquake in Eltabbar—then compel him to sit in Thakorsil's Seat, which immediately imprisoned him again. He then began the terrible task of performing the ritual of twin burnings and inscribing the runes of chaos upon the Seat to make Eltab his eternal slave. This generated a magical damping effect over central Thay, reducing the efficacy of divination spells and completely blocking them around Thaymount, preventing the Simbul of Aglarond from scrying on events in Thay. During this time, the Death Moon Orb hovered in place over Eltab in Thakorsil's Seat in the Chambers of Twin Burnings.

Nathor, a Thayan civil servant, bore witness to much of Szass Tam's wicked deeds, and saw Eltab seated on Thakorsil's Seat. Nathor later fled to Aglarond in horror.

However, before Szass Tam could inscribe the ninth and last rune of chaos, a band of mighty adventurers, armed with the greatsword Hadryllis, got into the Chambers and foiled his scheme. A terrific explosion shattered the crystal pyramid and the runes of chaos, releasing Eltab. Thakorsil's Seat was buried in the subsequent destruction of the Chambers.

Szass Tam eventually retrieved the Seat by 1372 DR, and stored it in his Citadel on Thaymount. It was still there in 1479 DR.

Destruction
Several possible methods were proposed for destroying Thakorsil's Seat. Firstly, it might be obliterated by being struck by a weapon swung by a greater deity. Secondly, it could be taken to the Abyss and dropped into the great forge belonging to the balor prince Vrr'maal. Thirdly, 100 wizards of great power could arrange themselves in a circle and hurl destructive magic at it for 100 days.

Lore
In the library of the Chambers of Twin Burnings, Szass Tam owned historical texts that covered Thakorsil's Seat and the Runes of Chaos.

A number of "false Seats" were in circulation, similar in appearance but lacking any powers. These had been built by wizards who sought to create their own devices of enslavement and failed. Adventurers were naturally more like to find one of these than the genuine article.

Reputation
Thakorsil's Seat was a tremendously powerful magic item yet was also unspeakably evil and utterly corrupting. Any attempt to perform the ritual of twin burnings, create the runes of chaos, or use Thakorsil's Seat to trap and bind another being was considered a terribly evil deed and grounds for punishment. It was a device many believed should never fall into the wrong hands—unfortunately, it was already in them: Szass's Tam's. With the horrific rites required and the total enslavement of potent beings, Thakorsil's Seat could well lead to continent-wide warfare and strife.