Apep, god of chaos

Alter Size. Apep can make himself any size between medium and gargantuan as a bonus action. His statistics other than his size do not change.

Aura of Fear. When a lawful or good aligned creature starts its turn within 240 feet of Apep, it must succeed on a DC 27 Wisdom saving throw or become frightened of Apep for 1 minute. If the creature is lawful good, it has disadvantage on this saving throw. 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 Apep’s Aura of Fear for the next 24 hours.

Chameleon Aura. Apep and all allies within 30 ft. of him have advantage on Dexterity (Stealth) checks.

Innate Spellcasting. Apep’s innate spellcasting ability is Charisma (spell save DC 27, +19 to hit with spell attacks). Apep can cast the following spells, needing only verbal components:

At will: chill touch, darkness, disguise self(can appear as a humanoid or giant), invisibility, telekinesis

3/day each: blink, charm person, dimension door, dispel magic, dominate person, mirror image, modify memory, pass without trace, polymorph

1/day: divine word

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

Limited Magic Immunity. Unless he wishes to be affected, Apep is immune to spells of 6th level or lower. He has advantage on saving throws against all other spells and magical effects.

Magic Weapons. Apep’s weapon attacks are magical.

Regeneration. Apep regains 30 hit points at the start of his turn if he has at least 1 hit point.

Multiattack. Apep makes one bite attack and one constrict attack.

Bite. Melee Weapon Attack: +19 to hit, reach 10 ft., one creature. Hit: 32 (4d10 + 10) piercing damage plus 18 (4d8) poison damage.

Constrict. Melee Weapon Attack: +19 to hit, reach 10 ft., one creature. Hit: 28 (4d8 + 10) bludgeoning damage, and the target is grappled (escape DC 20). Until this grapple ends, the creature is restrained, and Apep can't constrict another target.

Apep can take 5 legendary actions, choosing from the options listed. Only one legendary action option can be used at a time and only at the end of another creature's turn. Apep regains spent legendary actions at the start of his turn.

Spell. Apep casts a spell with a casting time of 1 action.

Attack (Costs 2 Actions). Apep uses his multiattack.

Invoke Duplicity (Costs 3 Actions). Apep creates up to 4 perfect illusions of himself that last for 1 minute, or until he uses this legendary action again. The illusions appear in unoccupied spaces that he can see within 30 feet. As a bonus action on his turn, he can move any of the illusions up to 30 feet to a space he can see, but each must remain within 120 feet of him. For the duration, Apep can cast spells as though he were in an illusion's space, but he must use his own senses. Additionally, when both Apep and an illusion are within 5 feet of a creature that can see the illusion, he has advantage on attack rolls against that creature, given how distracting the illusion is to the target.

Invulnerability (Costs 5 Action). Apep gives himself immunity to all damage except radiant damage until the end of his next turn.