Asmodeus

Fiendish Reawakening. When Asmodeus is reduced to 0 HP he instantly gains 510 HP and gains any expended Legendary Resistance and recharges Incinerating Hands. Additionally Asmodeus gains access to Mythic Actions for 1 Hour and regains any used spellcasting. If Asmodeus is defeated after Fiendish Reawakening award an additional 155,00 for a total of 310,000 XP. 

Legendary Resistance(5/day). If Asmodeus fails a saving throw he can succeed instead.  

Regeneration. Asmodeus regains 100 HP at the start of his turn, if he takes Radiant damage then this trait doesn’t activate. 

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

Multiattack. Asmodeus makes three Ruby Rod of Asmodeus attacks, he can replace one of the attacks with Incinerating Hands if able. 

Ruby Rod of Asmodeus. Melee weapon attack. +19 to hit, reach 10 ft., one target. Hit: 12d12 bludgeoning damage plus 12d8 fire damage.

Incinerating Hands. Asmodeus exhales a 150 ft cone from his hands, each creature in this area must make a DC 27 Dexterity saving throw or take 11d12 fire damage, additionally if the target is reduced to 0 hit points by this attack, the creature’s body is destroyed in the flames. 

Spellcasting. Asmodeus casts one of the following spells, requiring no material components and using Charisma as the spellcasting ability. 

At Will: fireball(acts as if casted at 9th level), alter self(can become Medium when changing appearance), wall of fire, major image, inflict wounds

6/day each: dispel evil and good, dominate monster, hold person, earthquake, finger of death. 

3/day: Power Word Kill, 

Summon Devils(Recharges after a long or short rest). Asmodeus summons 2d6 fiends of his choice, who follow his commands and remain until he dies or uses an action or bonus action to dismiss them.

Asmodeus 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. Asmodeus regains spent legendary actions at the start of its turn.

Attack. Asmodeus makes a Ruby Rod of Asmodeus attack. 

Sphere of Flames(costs 2 actions). Flames surround Asmodeus in a 300 ft sphere, any creature in this area must make a DC 27 Dexterity throw, taking 13d12 fire damage, half as much on a successful save. 

Spellcasting. Asmodeus Uses Spellcasting 

If Asmodeus' Fiendish Reawakening has activated in the last hour he can use his Mythic Actions below as legendary actions

Mind Attack(costs 2 actions). Asmodeus targets one creature with an intelligence of 8 or higher, that creature must make a DC23 Wisdom saving throw, taking 12d10 psychic damage, half as much on a successful one. 

Wrath of the Hells(Costs 3 actions). Asmodeus opens a 300 ft wide portal that hurls fireballs out of it, any creature in that area must make a DC 27 Dexterity throw or take 15d12 fire damage.