Avatar of Zarak, God of Chaos

Legendary Resistance (4/Day). If the Avatar fails a saving throw, it can choose to succeed instead.

Reality Warp. Zarak exerts his will on reality within a 60 ft. radius. Creatures starting their turn within the radius must succeed on a DC 20 intelligence saving throw or be affected by an extreme random change of reality, such as gravity shifting or time distortion (Choose one random effect from a DM-created table of chaotic outcomes). On a failure, the saving creature takes 50 (10d10) force damage and suffers extreme temporal confusion (cannot take reactions or bonus actions until the end of its next turn).

Innate Spellcasting. Zarak's spellcasting ability is Charisma (spell save DC 25, +17 to hit with spell attacks). He can innately cast the following spells, requiring no material components:

At will: dispel magic, mirror image, phantasmal force;

3/day each: reverse gravity, disintegrate, time stop;

1/day each: power word kill, prismatic wall, wish.

Chaotic Aura. Any creature within 20 feet of Zarak must make a DC 22 Charisma saving throw at the start of their turn. On a failed save, they are under the effects of the Confusion spell for 1 minute. The creature may repeat the save at the end of each of its turns, ending the effect on a success.

Necron Machine Surge. When reduced to below half hit points, Zarak's Necron form surges with catastrophic energy. Roll a d6. On a 1-3 Zarak radiates a pulse of pure entropy within 60 feet. All creatures in range must succeed on a DC 24 Constitution saving throw or take 80 (15d10) radiant or necrotic damage (Zarak's choice). On a 4-6, Zarak cannot be targeted by any attack or spell until the start of his next turn—randomly teleporting up to 200 ft. in any direction.

Multiattack. Zarak attacks three times: once with his Chaotic Claw and twice with his Celestial Disruptor Beam.

Chaotic Claw. Melee Weapon Attack: +18 to hit, reach 10 ft., one target. Hit: 46 (5d10 + 14) slashing damage and 24 (4d8) psychic damage. If the target is a creature, it must succeed on a DC 22 Dexterity saving throw or be enveloped in chaotic energy, leaving it stunned until the end of Zarak's next turn.

Celestial Disruptor Beam. Ranged Spell Attack: +17 to hit, range 300 ft., one target. Hit: 60 (8d12+6) necrotic damage. If the target is a nonmagical item, it is immediately disintegrated. Creatures within 10 ft. of the target must succeed on a DC 22 Dexterity saving throw or take 40 (6d10) thunder damage.

Fracture Space (Recharge 5-6). Zarak tears the fabric of reality, creating a 30 ft. radius of warped space centered on a point within 100 ft. Creatures within the radius immediately teleport to random locations within 1d12 x 50 ft. in any direction, taking 45 (10d8) force damage.

Gaze of Total Chaos (recharge 6). Zarak chooses one target within 120 ft. to make eye contact. The target must succeed on a DC 24 Wisdom saving throw or be thrown backwards through the planes. The creature is banished to a random plane of Zarak's choice for 1d4 rounds. Upon returning to their original plane, the creature takes 70 (15d10) psychic damage and is permanently blinded until healed by the Wish spell or similar means.

Celestial Machine Form. Zarak's fractured nature allows him to exist in multiple dimensions simultaneously. As a reaction to being targeted by an attack, he can shift to an alternate timeline—imposing disadvantage on all attacks against him until the start of his next turn. This can be used 3 times per day.

The avatar can take 4 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 avatar regains spent legendary actions at the start of its turn.

Flicker in Time. Zarak moves up to his speed, phasing through solid objects as if they weren't there. This movement doesn't provoke opportunity attacks.

Disrupt Timeline (Costs 2 Actions). Zarak reverses or advances time slightly for a creature within 120 ft. The creature must succeed on a DC 24 Intelligence saving throw or take 50 (9d10) psychic damage and lose their reaction and bonus action on their next turn.

Rend Reality (Costs 2 Actions). Zarak targets a point within 120 ft. and tears open the boundaries of reality. A chaotic portal appears for 1 minute. Any creature passing through the portal must succeed on a DC 23 Constitution saving throw or take 60 (10d10) radiant or necrotic damage (DM's choice) and be stunned for 1 minute.

Chaotic Surge (Costs 3 Actions). Zarak unleashes a pulse of chaotic energy in a 90 ft cube. All creatures within cube must make a DC 20 Constitution saving throw or take 45 radiant damage and be thrown prone, the gravity, magnetic field, or space randomly distorts users failing.