Arch devil Sharruk of Maladomini

Curse of Lies. Any non fiend that starts its turn within 20ft of Sharruk must make a DC 23 Wisdom saving throw, unless he is incapacitated. Unless the save succeeds, the creature can’t tell a truth in that radius and if they fail by 10 or more, they are stunned until the start of their next turn. Anyone who succeeds this save is immune to this effect for the next 24 hours.

Cursed Weapons. Sharruk’s weapon attacks are magical. When he hits with any weapon, the weapon deals an extra 21 (6d6) necrotic damage (included in the weapon attacks below).

Innate Spellcasting. Sharruk’s spellcasting ability is Charisma (spell save DC  23, +14 to hit with spell attacks). He can innately cast the following spells, requiring no material components:

At will: aganazzar’s scorcher (as a 7th-level spell), bestow curse, chaos bolt (as a 7th-level spell), detect magic, fire ball, fly, suggestion
3/day: dispel magic, hold monster, dominate person, modify memory, regenerate 
1/day: dominate monster, finger of death, power word kill, teleport

Legendary Resistance (3/Day). If Sharruk fails a saving throw, he can choose to succeed instead.

Magic Resistance. Sharruk has advantage on saving throws against spells and other magical effects.

Regeneration. Sharruk regains 20 hit points at the start of his turn. If he takes radiant damage, this trait doesn’t function at the start of his next turn. Sharruk dies if he starts his turn with 0 hit points and doesn’t regenerate.

Soul Eater. Sharruk can take a bonus action to eat a soul he has killed in the last turn or he has gathered from his Soul Reap action to gain 36 temporary hit points  for 1 minute and advantage on hit next attacks while he still has temporary hit points or for the duration of the ability

Action Name. Sharruk can make three attacks: two with his poleaxe and one with his bite or overload if it is available.

Poleaxe. Melee Weapon Attack: +16 to hit, reach 15 ft., one target. Hit: 23 (3d10 + 7) slashing damage, plus 21 (6d6) necrotic damage. If Sharruk wishes a creature that is huge or smaller hit by this attack must succeed on a DC 23 Strength saving throw or be pushed 10ft away from him.

Bite. RangedWeapon Attack: +16 to hit, range 5 ft., one target. Hit: 10 (2d6 + 7) piercing damage plus 21 (6d6) necrotic damage.

Reap Soul (1/Day). Sharruk targets a creature that has less than all its hit points and doesn’t have temporary hit points, that target must make a DC 23 Charisma saving throw or take 50 (10d10) necrotic damage, this damage reduces the targets maximum hit points equal to the the necrotic damage taken, if it reduces the target’s maximum hit points to 0 their soul is reaped from their body and they die, on a successful save the target takes half the necrotic damage and their maximum hit points are not reduced.

Overload (Recharge 7–8). Sharruk assumes a form of battle and goes overload. All creatures in 10ft radius of Sharruk must succeed on a DC 23 Constitution saving throw or be pushed back 10ft and takes 21 (6d6) force damage. Or all creatures in a 30ft by 5ft line must make the same save for the same effects.

Teleport. Sharruk magically teleports, along with any equipment he is wearing or carrying, up to 120ft to an unoccupied space he can see.

Sharruk can take 3 legendary actions, choosing from the options below. Only one legendary action option can be used at a time and only at the end of another creature’s turn. Sharruk regains spent legendary actions at the start of his turn.

Poleaxe. Sharruk attacks once with his poleaxe 
Frightful Gaze (Costs 2 Actions). Sharruk targets a creature he can see in 120ft and grins maniacally. The target must succeed on a DC 23 Wisdom saving throw or be frightened of Sharruk for 1d4 rounds, repeating the save at the ends of its turn.
Teleport. Sharruk uses his Teleport action.

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Mythic Action Name (Costs # Actions). Enter the description for your mythic action.