Avatar of Tharizdun

Cunning Action. On each of his turns, Tharizdun can use a bonus action to take the Dash, Disengage, or Hide action.

Evasion. When Tharizdun is subjected to an effect that allows you to make a Dexterity saving throw to take only half damage, he instead takes no damage if he succeeds on the saving throw, and only half damage if he fails.

Legendary Resistance (5/day). If Tharizdun fails a saving throw, he can choose to succeed instead.

Limited Magic Immunity. Unless he wishes to be affected, Tharizdun is immune to spells of 6th level or lower. He has advantage on saving throws against all other spells and magical effects. When Tharizdun takes radiant damage, this feature ceases to function until the start of Tharizdun's next turn.

Maddening Visage.  When a creature starts its turn within 25 feet of Tharizdun or moves into this range on its turn, the creature must make a Wisdom Saving Throw (DC 26). On a failed save, the creature becomes frightened of Tharizdun and takes 4d10 Psychic damage. At the start of a creature's turn, it may intentionally avert its gaze away from Tharizdun in order to prevent this effect. Creatures averting their gaze have disadvantage on attack rolls against Tharizdun.

Magic Weapons. Tharizdun's weapon attacks are magical.

Reactive. Tharizdun can take three reactions each round.

Regeneration. Tharizdun regains 30 hit points at the start of its turn.

Sneak Attack (1/turn). Tharizdun deals an extra 60 (15d6) damage when it hits a target with a weapon attack and has advantage on the attack roll, or when the target is within 5 ft. of an ally of Tharizdun that isn't incapacitated and Tharizdun doesn't have disadvantage on the attack roll.

Innate Spellcasting. The avatar of tharizdun's spellcasting ability is Charisma (spell save DC 27). The avatar of tharizdun can innately cast the following spells, requiring no material components:

9/day each: Thunder Step 

Godly Speed (Recharge 5-6). Tharizdun moves faster than the eye can see.Tharizdun dashes past each creature with a 40-foot Radius, making an attack against each one. Tharizdun makes a single Short Sword attack that counts against the AC of each creature within range. On a hit, the creature suffers sneak attack damage as well (15d6).

Maddening Blast (Recharge 5-6). Tharizdun forces each creature within range to be effected by Maddening Visage unless they have averted their gaze. On a failed save, the effects of Maddening Visage are suffered immediately.

Short Sword. Melee Weapon Attack: +19 to hit, reach 5 ft., 1 target. Hit: 13 (1d6 + 10) piercing damage. 

Teleport Strike. Melee Weapon Attack: +19 to hit, reach 30 ft., 1 target. Hit: 38 (8d6 + 10) piercing damage.

Caustic Blood. Tharizdun's devine blood is infused with abyssal darkness. When Tharizdun is hit with an attack by a creature within 5 ft of him, he can use his reaction to cause an explosion of fiery blood. The attacker must make a DC 26 Dexterity saving throw. On a failed save, the attacker takes 7d6 fire damage, or half as much on a successful one.

Deflect Missiles. Tharizdun can use his reaction to deflect or catch a missile when he is hit by a ranged weapon attack. The attack can be physical or magical. When he does so, the damage he takes from the attack is reduced by 1d10+43. If he reduces the damage to 0, he can catch the missile if it is small enough to hold in one hand. If he catches a missile in this way, he can make a ranged attack with the weapon or piece of ammunition he just caught, as part of the same reaction. This attack has +19 to hit and deals 8d6 damage. It has a normal range of 20 ft and a long range of 60ft.

Uncanny Dodge. When an attacker Tharizdun can see hits him with an attack, he can use a reaction to halve the attack's damage against him.

The avatar of tharizdun can take 3 legendary actions, choosing from the options below. Only one legendary action can be used at a time and only at the end of another creature's turn. The avatar of tharizdun regains spent legendary actions at the start of its turn.

Teleport Strike. Tharizdun uses his Teleport Strike ability.

Thunder Step. Tharizdun casts the spell Thunder Step.

Sword Sword. Tharizdun makes a Short Sword attack. 

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Mythic Action Name (Costs # Actions). Enter the description for your mythic action.