K'Varn

K'varn the Mad is a Beholder in the D&D podcast webseries, Critical Role. He serves as the primary antagonist of the first chapter, the "Underdark Arc", beginning in Episode 1 "Arrival at Kraghammer" and ending in Episode 16 "Enter Vasselheim" (although, K'Varn is defeated in Episode 11 "The Temple Showdown"). K'Varn is a powerful self-mutated Beholder, who uses "The Horn of Orcus" to take control of the Underdark. Like all NPCs, K'Varn is created and voiced by the DM, Matt Mercer.

Pre-Game
K'Varn, like most Beholders, originally came from the Far Realm, another dimension parallel to the Material Plane. At some point, and through means unknown, he became aware of The Horn of Orcus, which was literally one of two horns of the Arch-Demon that had broken off. Pulling it through to his plane, he fused it to his forehead, and made his way to the Material Plane.

He would enter near Yug'Voril, an Illithid city in the Underdark, beneath the Dwarven city of Kraghammer. First moving to the duergar city of Emberhold, K'Varn used his superior power and intellect to overcome their forces and enslave them. After capturing and most likely torturing and questioning a lone Illithid, K'Varn used his new duergar army to attack Yug'Voril, distracting them long enough to infiltrate the elder brain's chamber and take control of it. In doing so, he subsequently controlled the illithid throught the elder brain's hive mind.

With control of both armies, he began to plot an invasion of the surface world. He slowly began to expand his territory, capturing other denizens of the Underdark and using his new power to twist and reshape them into "stitch monsters", horrible abberations he planned to use as soldiers in the coming war. He similarly began to reshape his own form, welding "armor" onto his sides. He began to move his forces further up, encroaching into the mines of Kraghammer and attacking the dwarven miners.

Eventually he got the attention of Lady Kima, a paladin of Bahamut who knew of his evil item. Kima traveled to Kraghammer to stop his great evil, but was captured by his duergar forces and held in Emberhold by King Murghol. This led her "friend", Lady Allura to seeking out our heroes, Vox Machina.

During the Journey Downward
While Vox Machina found the entrance to the Underdark shortly after their arrival in Kraghammer, they would not first hear of K'Varn until episode 3, "Strange Bedfellows". After fighting a band of duergar, they take one prisoner, and questioned her. She revealed her people were helping craft the "stitch monsters" and that they served him. The party would receive other cryptic hints of something bigger, such as when they met their friend and teammate, Pike, War Cleric of Sarenrae, who said she was guided here by dark visions (probably the same ones that guided Kima). They heard his name again from Clarota, a rogue illithid they made a tenuous alliance with. He told them that he had united his people and the duergar and planned to grow his army.

Eventually learning of the Horn as well and after dealing with several incursions with the duergar, they finally meet him in episode 9, "Yug'Voril Uncovered", during a battle with the duergar queen, Ulara. He possesses her body to greet and threaten the group, "welcoming" them to his Underdark and telling them that he expects them within Yug'Voril. He then psychically killed the queen.

Keyleth, Vox Machina's druid is the first party member to make direct contact with K'Varn. As the party rested in preparation for their battle with, not only K'Varn, but they expect an entire city of mind flayers, Keyleth attempted to scry on him in his chamber. In her spirit form, she saw his chamber and she learned what he truly was, a mad, mutated Beholder. She also saw a crystal structure he had built around the elder brain to secure his hold on it. K'Varn, sensing her scry, psychically attacked her, forcing her to retreat. The revelation of what he is and what he had done scared a few of the party, especially their sorcerer, Tiberius Stormwind.

The Temple Showdown
As they made their way to the temple that K'Varn had holed himself in, the party came across and captured a fomorian, a dark, evil giant. First transforming him into a small creature, they dropped him from high above and changed him back as he hit the crystal structure around the temple, freeing the elder brain and, in the process, the illithid. As the party assaulted K'Varn from above, Tiberius, fearing a direct confrontation, fled to try and enlist the help of the illithid (to...less than stellar results).

While many of the party attempted to attack from the relative safety of the roof, others were forced (sometimes by K'Varn's own power) to enter and take him head on. K'Varn's abilities proved formidable, and he took out several of the members. Lady Kima (whom the party rescued earlier), was turned to stone by one of his eye beams as she attacked him. Barbarian Grog attempted to yank the Horn from K'Varn's head and was killed in the process (after blasting him down, K'Varn notably floated above him and gloated "who's next"). Grog was, thankfully, saved by a well timed Revivify on Pike's part.

Eventually, he was whiddled down and taken out by the team's ranger, Vex'ahlia. However, their victory was short-lived as the Horn brought K'Varn back to life as a zombie (Orcus is a lord of undeath, afterall). After some further battling, the party was saved by a returning Tiberius who used telekinesis to pull the Horn from K'Varn's head. The resulting blow undid the raising, and the corpse of K'Varn fell limp once more.

Aftermath
Following the battle with K'Varn, the party then had to deal with the incoming illithid, including Clarota, who betrayed them to get back with his own kind. After killing Clarota and the immediate mind flayers (and hurting the elder brain), the party flew off and escaped through one of Tiberius's teleportation circles.

The resulting death of K'Varn has left the Underdark in a mass of chaos once more. The unified army has separated again (so it is assumed). The duergar are badly crippled by their infiltrated base and lost monarchs. The damages to the illithid are largely unknown. While the brain was hurt by Vox Machina, they retained the abberations created by K'Varn, so they may still be a force to be reckoned with. The council of Emon did not see them as an immediate threat, though.

Vox Machina were able to escape with the Horn of Orcus. Under the advice of Lady Kima and with the consent of Emon, they brought it to her people in Vasselheim, who had the group seal it in their vault in the Platinum Sanctuary. To anyone's knowledge it still resides there.