Bartimeus

Elemental Restoration. If the djinni dies outside the Elemental Plane of Air, its body dissolves into mist, and it gains a new body in 1d4 days, reviving with all its Hit Points somewhere on the Plane of Air.

Magic Resistance. The djinni has Advantage on saving throws against spells and other magical effects.

Multiattack. The djinni makes three attacks, using Storm Blade or Storm Bolt in any combination.

Shifting Strike. Melee Weapon Attack: +8 to hit, reach 5 ft., one target.
Hit: 10 (2d6 + 3) bludgeoning damage plus 9 (2d8) psychic damage, as Bartimeus briefly shifts into a terrifying form, assaulting both the body and the mind of the target.

Arcane Sneer. Ranged Spell Attack: +8 to hit, range 60 ft., one target.
Hit: 14 (4d6) force damage. The target must succeed on a DC 16 Wisdom saving throw or be frightened until the end of its next turn.

Formshift Manifestation. Bartimeus assumes a dramatic alternate form — gargoyle, winged serpent, lion-headed warrior, or other — at a point he can see within 30 feet. Each hostile creature within 10 feet of this form must succeed on a DC 16 Wisdom saving throw or be Stunned until the end of its next turn. He can maintain this manifestation as Concentration, changing its appearance at will.

Illusory Legion. Bartimeus summons a swarm of illusory duplicates within a 15-foot radius centered on himself. These phantasms flicker between shapes, granting him the benefits of the Mirror Image spell. Additionally, any creature starting its turn in the area must succeed on a DC 16 Intelligence saving throw or be unable to distinguish illusions from reality, giving it disadvantage on attack rolls until the start of its next turn.

Spellcasting. Bartimeus casts one of the following spells, requiring no Material components and using Charisma as the spellcasting ability (spell save DC 16):

• At Will: Disguise Self, Minor Illusion, Detect Magic

• 3/Day Each: Invisibility, Suggestion, Misty Step

• 1/Day Each: Major Image, Phantasmal Killer, Plane Shift (self only)