Zerxus, Champion of the Nine Hells

Battle Readiness. Zerxus has advantage on initiative rolls.

Improved Critical. Zerxus' attack rolls score a critical hit on a roll of 19 or 20 on the d20.

Arm of the Betrayer. The champion of Asmodeus wields Mace of the Black Crown (Awakened) and is attuned to it.

Legendary Resistance. If Zerxus fails a saving throw, he can choose to succeed instead.

Extra Attack. Zerxus can attack three times, instead of once, whenever it takes the attack action on its turn.

 Mace. Melee Weapon Attack:+10 to hit, reach 5ft., one target. Hit: 12 (2d6 + 5) Bludgeoning damage plus 20 (4d6) fire damage.

Summon Devil. As an action, you may use the mace to summon a bearded devil to aid you in combat.

Spellcasting. Zerxus' innate spellcasting ability is Charisma (spell save DC 18, +10 to hit with spell attacks). He has the following spells prepared:

2nd level (4 per long rest): Wrathful Smite, Burning Hands, Zone of Truth

3rd level (3 per long rest): Searing Smite, Blinding Smite, Counterspell(Can upcast up to 5th level)

 5th level (2 per long rest): Destructive Wave, Banishment

Torment of the Nine Hells. When Zerxus is below half Hit Points, he may use his bonus action to cast Dissonant Whispers at 3rd level. The targeted creature heres the sounds of torture and pain Zerxus lived through for years.

Champion's Rage. As a reaction, Zerxus lashes out at an enemy that has damaged him, casting Hellish Rebuke at 3rd level.

The Champion of the Nine Hells 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. Zerxus regains spent legendary actions at the start of its turn.

Cleansed in Flame. Zerxus can spend on of his legendary actions to use Cleansing Touch on himself or another willing creature, ridding them of any effect or spell currently afflicting them.

Rage of Asmodeus. Upon being hit by a Melee Attack, Zerxus may spent one legendary action to make a single [Tooltip Not Found] using the Mace of the Black Crown (Awakened).