Asmodeus

Innate Spellcasting Asmodeus' innate spellcasting ability is Intelligence (Spell save DC 30, +25 to hit). Asmodeus can cast the following spells without needing components or expending a spell slot:

At will. Frostbite, Toll the dead, Inflict wounds, Thunderous smite, Pyrotechnics, Scorching ray, Bestow curse, Vampiric touch, Blight, Wall of fire, Cone of cold, Destructive wave, Raise dead, Create undead, Soul Cage, and Wall of ice

3/day each. Finger of Death, and Fire storm

1/day each. Power Word Stun, and Power Word Kill

Regeneration. Asmodeus regains 90 hit points at the start of his turn as long as he hasn't taken any radiant damage.

Multiattack. Asmodeus can use his frightful presence. He then makes five attacks with  his Ruby Rod, and then one with his horns.

Ruby Rod. Melee Weapon Attack: +18 to hit, reach 10 ft., one target. Hit: 51 (8d8 + 15 ) piercing damage.

Ruby Rod (Ranged).Ranged Weapon Attack: +14 to hit, 150/600 ft., one target. Hit: 40 (9d8) fire damage or 45 (10d8) lightning damage.

Horns Melee Attack: +14 to hit, 4d4 piercing damage. The target must succeed on a DC 20 Charisma saving throw or get poisoned. The target may roll again every day or until a spell such as lesser restoration is cast.

Frightful Presence. Each creature of Asmodeus’s choice that is within 200 feet of Asmodeus and aware of him must succeed on a DC 20 Wisdom saving throw or become frightened for 1 minute. A creature can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success. If a creature’s saving throw is successful or the effect ends for it, the creature is immune to Asmodeus's Frightful Presence.

Soul Bartering. Asmodeus can grant any humanoid one wish (using the spell wish) in its lifetime on the condition that the PC is bound to him after death. Asmodeus can make minor changes to the wishes if he wants. Asmodeus suffers no harmful effects from this action.

Innate Spellcasting. As a bonus Action, Asmodeus can innately cast one spell.

Now you see me. As a bonus action on his turn, Asmodeus can teleport anywhere within his line of sight or in the nine hells.

Loyalty to the Lord. As a bonus action, if Asmodeus' rod was ever knocked or taken out of his hand, he can instantly recall it back to him.

The Asmodeus can take 5 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. The Asmodeus regains spent legendary actions at the start of its turn.

Chilling Gaze (Costs 1 Action). Asmodeus target one creature within 30 ft., the target makes a Wisdom Save of DC 23 on a failed save target takes 3d10 psychic damage, and gains 1 level of exhaustion. On gaining six levels of exhaustion creature is dominated by Asmodeus.

Hell's Gate (Costs 2 Actions). As the King of the Hells, Asmodeus has absolute control over all of the gates and portals within Hell. The Lord of the Nine can cause a gate or portal to open, sucking in those within 60 feet into a location in the Nine Hells of Asmodeus' choosing if they fail a DC 15 Dexterity Save. The Mouth remains open for 3 rounds. A Hell's Mouth appears as a great, diabolically evil human male face with jagged, chewing teeth. Flames burst from the gaping maw as it attempts to suck in unlucky victims.

Call of the Lord (Costs 2 actions). Asmodeus can summon eight Chain Devils

Innate Spellcasting (Cantrip costs 1 action, 3/Day costs 3 actions, and 1/day costs 4 actions). Asmodeus can cast one spell.