Archduke Levistus of Stygia

Devil’s Sight. Magical darkness doesn’t impede Levistus' darkvision.

Icy Weapons. Levistus' weapon attacks are magical. When he hits with any weapon, the weapon deals an extra 27 (6d8) cold damage (included in the weapon attacks below).

Innate Spellcasting. Levistus' innate spellcasting ability is Charisma (spell save DC 26, +16 to hit). He can innately cast the following spells, requiring no material components:

At will: disguise self, detect evil and good, darkness, invisibility (self only), ray of frost, ice storm wall of force, charm person, suggestion, mirror image, major image, see invisibility

3/day each: blade barrier, dispel evil and good, finger of death, greater invisibility, cone of cold, dispel magic, shield, wall of ice, banishment, forcecage, plane shift

1/day each:prismatic wall, feeblemind, glibness

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

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

Regeneration. Levistus 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. Levistus dies only if he starts his turn with 0 hit points and doesn’t regenerate.

Multiattack. Levistus attacks three times with his rapier, or twice and uses teleport or amnesia touch.

Rapier. Melee Weapon Attack: +16 to hit, reach 5 feet, one target. Hit: 27 (4d8 + 9) piercing damage plus 27 (6d8) cold damage.

Amnesia Touch. Levistus touches a creature within 5 feet of him. The creature must make a DC 26 wisdom saving throw or forget all details and events of the last 24 hours, as though under the effects of modify memory.

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

Sneak Attack. If Levistus has advantage on an attack roll, or if another enemy of the target is within 5 feet of it, the enemy isn't incapacitated, and he doesn't have disadvantage on the attack roll, he can choose to deal an extra 10d6 damage of the weapon's damage type.

Fiendish Cunning. Levistus can take the dash, disengage, dodge, or hide action as a bonus action on his turn.

Elaborate Parry. Levistus adds 6 to his AC against one melee attack that would hit him. To do this, Levistus must see the attacker and be wielding a melee weapon.

Spell Parry. If Levistus makes a successful saving throw against a spell, or a spell attack misses him, he can choose another creature (including the spellcaster) within 120 feet to be the target of the spell instead, with Levistus' spellcasting modifier.

Levistus 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. Levistus regains spent legendary actions at the start of his turn.

Rapier (Costs 1 Action). Levistus makes a rapier attack.

Icy Gaze (Costs 2 Actions). Levistus targets one creature that he can see that has been affected by Icy Weapons within the last turn. That creature must make a DC 26 constitution saving throw or take one level of exhaustion, and its movement speed is halved for the next minute. It takes a -2 AC penalty, and has disadvantage on dexterity saving throws. On its turn, it can either use an action or a bonus action, but not both. It can repeat the saving throw at the end of its turn. If it fails three times, it takes 10d10 cold damage and is encased in solid ice. While encased in this way, it can take no actions or reactions, cast no spells, and its movement speed is reduced to 0. The ice can only be melted by greater restoration or a dragon's fire breath.

Teleport. Levistus uses his Teleport action.