Huge elemental, neutral evil

Armor Class 22

Hit Points 283 (21d12+147)

Speed 50 ft., fly 150 ft.

STR DEX CON INT WIS CHA
18 (+4) 24 (+7) 24 (+7) 16 (+3) 21 (+5) 23 (+6)

Saving Throws Dex +13, Wis +11, Cha +12

Damage Resistances cold, fire, bludgeoning, piercing, and slashing from nonmagical weapons

Damage Immunities lightning, poison, thunder

Condition Immunities charmed, frightened, paralyzed, petrified, poisoned, prone, restrained

Senses blindsight 120 ft., passive perception 15

Languages Auran

Challenge 18 (20,000 XP)

Air Form Yan-C-Bin can enter a hostile creature’s space and stop there. He can move through a space as narrow as 1 inch wide without squeezing if air could pass through that space.

Empowered Attacks. Yan-C-Bin’s slam attacks are treated as magical for the purpose of bypassing resistance and immunity to nonmagical weapons.

Innate Spellcasting. Yan-C-Bin’s innate spellcasting ability is Charisma (spell save DC 20, +12 to hit with spell attacks). He can innately cast the following spells, requiring no material components:

  • At will: gust of wind, invisibility, lightning bolt

  • 2/day each: chain lightning, cloudkill, haste

Legendary Resistance (3/Day). If Yan-C-Bin fails a saving throw, he can choose to succeed instead.

Magic Resistance. Yan-C-Bin has advantage on saving throws against spells and other magical effects.

Actions

Multiattack. Yan-C-Bin makes two slam attacks.

Slam. Melee Weapon Attack: +14 to hit, reach 10 ft., one target. Hit: 20 (3d8 + 7) force damage plus 10 (3d6) lightning damage.

Thundercrack (Recharges after a Short or Long Rest). Yan-C-Bin unleashes a terrible thundercrack in a 100-foot-radius sphere centered on himself. All other creatures in the area must succeed on a DC 24 Constitution saving throw or take 31 (9d6) thunder damage and be deafened for 1 minute. On a successful save, a creature takes half as much damage and is deafened until the start of Yan-C-Bin’s next turn.

Change Shape. Yan-C-Bin polymorphs into a Medium humanoid. While in polymorphed form, a swirling breeze surrounds him, his eyes are pale and cloudy, and he loses the Air Form trait. He can remain in polymorphed form for up to 1 hour. Reverting to his true form requires an action.

Summon Elementals (1/Day). Yan-C-Bin summons up to three air elementals and loses 30 hit points for each elemental he summons. Summoned elementals have maximum hit points, appear within 100 feet of Yan-C-Bin, and disappear if Yan-C-Bin is reduced to 0 hit points.

Legendary Actions

Yan-C-Bin can take 3 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. Yan-C-Bin regains spent legendary actions at the start of its turn.

Peal of Thunder. Yan-C-Bin unleashes a peal of thunder that can be heard out to a range of 300 feet. Each creature within 30 feet of Yan-C-Bin takes 5 (1d10) thunder damage.

Teleport (Costs 2 Actions). Yan-C-Bin magically teleports up to 120 feet to an unoccupied space he can see. Anything Yan-CBin is wearing or carrying is teleported with him.

Suffocate (Costs 3 Actions). Yan-C-Bin steals the air of one breathing creature he can see within 60 feet of him. The target must make a DC 21 Constitution saving throw. On a failed save, the target drops to 0 hit points and is dying. On a successful save, the target can’t breathe or speak until the start of its next turn.