Torment-Hardened. Xardorok has advantage on saving throws against poison, spells, and illusions, as well as to resist being charmed or paralyzed.

Spurred by Pain. While Xardorok is affected by an ongoing effect that ends on a successful saving throw, he can repeat that saving throw whenever he takes 10 or more damage from a single source.

Succumb to Corruption (Mythic Trait). When Xardorok is reduced to 0 Hit Points, he doesn’t die or fall unconscious. Instead, eldritch growths swell from his corrupted flesh, changing his max health to 170 and fully healing him. His size becomes Large (12 ft. tall), his speed increases to 40ft, and each condition affecting him ends. His Mythic Actions and bonus actions replace his current actions and bonus actions, and he can no longer cast hellish rebuke. His strength increases to 22, and his intelligence decreases to 7, and his armor class decreases to 16.

Unstable Growth. When Xardorok takes any Necrotic damage, if his mythic trait is active, his flesh softens and tears. Until the start of his next turn, attacks against him score a Critical Hit on an 18-20.

Multiattack. Xardorok makes two attacks with his Chardalyn Gauntlet, eldritch blast, or Hurl Flame, then can use his Profane Fate or Subjugation Array.

Chardalyn Gauntlet. Melee Weapon Attack: +7 to hit, reach 5 ft., one target. Hit: 13 (2d8 + 4) bludgeoning damage, and the target is pushed back 5 feet.

Eldritch Blast (Cantrip). Ranged Spell Attack: +7 to hit, range 120 ft., one creature. Hit: 9 (1d10 + 4) force damage.

Hurl Flame (Level 2 Spell). Ranged Spell Attack: +7 to hit, range 150 ft., one target. Hit: 14 (4d6) fire damage. On a Critical Hit, the target catches fire, and takes 5 (1d10) fire damage at the start of each of its turns until it or another creature that can reach it uses an action to smother the flames. If it is doused in water, takes any cold damage, or is in an airless environment, such as a bag of holding, the flames immediately go out.

Profane Fate (Level 2 Spell). Fate is corrupted, forcing one creature Xardorok can see within 60 feet to make a DC 15 Charisma saving throw. On a failed save, the creature becomes cursed for 1 minute. Whenever the cursed creature succeeds on a saving throw, Xardorok can choose to end this curse to cause it to fail the saving throw instead.

Subjugation Array (Recharge 5-6 Level 3 Spell, Concentration). Needles of dark crystal orbit a creature Xardorok can see within 60 feet, probing for weakness. At the start of each of the creature’s turns, it must make a DC 15 Wisdom saving throw. On a success, it takes 4 (1d8) psychic damage. On a failure, the creature becomes charmed by Xardorok until the end of its turn, at which point this effect ends. For the duration of the effect, the creature acts as if under the effects of the dominate person spell, with Xardorok as its master.

If Xardorok's mythic trait is active, he has the following bonus actions.

Flail Growths. Eldritch appendages thrash wildly, still wet with viscera. Each creature in a 5-foot radius from Xardorok must make a DC 14 Dexterity saving throw. On a failure, they take 9 (2d8) slashing damage.

Psionic Empowerment. Xardorok psionically produces one of the following effects:

• Telekinetic Leap. Xardorok jumps up to 40 feet.
• Psychic Screech. Each creature in a 30-foot Emanation from the duergar takes 4 (1d8) psychic damage. A creature with Telepathy has vulnerability to this damage.
• Mind Funeral. One creature Grappled by Xardorok must make a DC 14 Intelligence saving throw. On a failure, they take 22 (4d10) Psychic damage. A creature reduced to 0 Hit Points by this damage can only do one of the following things on their turn: move, use an action, or use a bonus action. This effect lasts until it completes a Long Rest.

Hellish Rebuke (2/Day). When Xardorok is damaged by a creature within 60 feet of him that he can see, the creature that damaged him is engulfed in hellish flames and must make a DC 15 Dexterity saving throw, taking 11 (2d10) fire damage on a failed save, or half as much damage on a successful one.

Elemental Imprint. Whenever Xardorok takes any Cold, Fire, or Lightning damage, he gains resistance to further damage of that type, and his melee attacks deal an additional 3 (1d6) damage of that type until the end of his next turn.

If Xardorok's mythic trait is active, the following actions replace his current ones.

Monstrous Fist. Melee Attack Roll: +9 to hit, reach 10 ft. Hit: 24 (4d8 + 6) bludgeoning damage and Xardorok can Grapple the target (escape DC 17).

Hurl Rubble. One target Xardorok can see within 30 feet must make a DC 17 Dexterity saving throw. On a failure, they take 26 (4d12) bludgeoning damage. If Xardorok has a creature Grappled, he can throw it; the thrown creature lands Prone in the nearest unoccupied space to the target and must make the same saving throw.