Heartless Angel: Adriel harnasses the warring energies to summon pillars of fire beneath his enemies, requiring a dexterity saving throw of 19 or higher taking 3d20 Radiant damage and 3d20 necrotic damage on a failed save and half as much on a successful save

Angelic Presence: The very presence of Adriel saps antagonistic foes of any strength they may be borrowing, such as paladin blessings or benefits from a patron, and gains strength due to his new found power. Adriel gains +2 to all stats for each of these borrowed powers active and cancels their effect. Adriel may spend his legendary action to activate the benefits on himself

Spellcasting. Adriel is a 20th level spellcaster. Its spellcasting ability is  (spell save DC 19, + 5 to hit with spell attacks). Adriel has can cast spells without material components due to his angelic power as well as his demonic and draconic souls

Adriel has access to the following spells at will:

Fireball, Meteor Storm, Sunburst, Greater Restoration, Ice Storm, Banishment and Gate

Claw Strike: Transforms or uses a draconic claw to swipe at a target

+5 to hit

2d6 +6 slashing damage

Action Melee Attack. Divine Spear 

5 ft range melee strike 70 ft range projectile

+5 to hit

4d10 radiant damage

Angelic Grace: As a reaction Adriel can any magical damage taken by his armour class plus his Challenge Rating. Adriel can also reduce any incoming damage dealt my a non demonic weapon by half

Adriel gains 3 Mythic action per turn (to a max of 3) and can be spent in the following ways:

EX Heartless Angel (Costs 1 Action with a 3 turn cooldown): Heartless Angel is performed on a massive scale utilising unprecedented amounts of Demonic and Angelic power. This attack summons a purple halo above any target that apply a mark. This mark detonates for 1d100 damage that is split between Necrotic and Radiant damage. 

Angelic Presence EX (Costs 2 Actions): See Angelic Presence 

Harmonic Destruction (Costs 3 Actions): Adriel begins to combine Draconic and Amgelic power and begins to prioritise strikes with his Spear of Harmony gaining an extra 3 attacks per action in which one must be used to make a claw strike

Harmonic Invigoration (Only available after Harmonic Destruction, Costs 3 Actions): Adriel combines his 4 warring natures and becomes a being of fearsome power. He loses access to his spear and armour class as well as his ability to cast spells. Adreil's Hit Points becomes 1,500 and he gains access to Harmonic Strike, a hit dice of 1d20 and a damage dice of 12d6 that hits in a 6 ft crescent. This transformation summons 3 demonic swords and 3 angelic spears the former hitting for 2d10 and the latter hitting for 2d6. Demonic blades target bystanders of attacks while the spears target the primary target.