Thuellai
Huge elemental, chaotic neutral
Armor Class
17
Hit Points
149 (13d12 + 65)
Speed
0 ft., fly 100 ft. (hover)
STR
22 (+6)
DEX
24 (+7)
CON
20 (+5)
INT
10 (+0)
WIS
11 (+0)
CHA
14 (+2)
Damage Immunities
poison
Damage Resistances
lightning, thunder; bludgeoning, piercing, and slashing from nonmagical weapons
Damage Vulnerabilities
fire
Condition Immunities
exhaustion, grappled, paralyzed, petrified, poisoned, prone, restrained, unconscious
Senses
darkvision 60 ft., passive Perception 14
Saving Throws
Int +4, Wis +4, Cha +6
Skills
Perception +4
Languages
Common, Dwarvish, Primordial
Challenge
10 (5900 XP)
Air Mastery. Airborne creatures have disadvantage on attack rolls against the thuellai.
Snow Vision. The thuellai see perfectly well in snowy conditions. It does not suffer Wisdom (Perception) penalties from snow, whiteout, or snow blindness.
Actions
Multiattack. The thuellai makes two claw attacks.
Claw. Melee Weapon Attack: +10 to hit, reach 10 ft., one target. Hit: 15 (2d8 + 6) slashing damage plus 26 (4d12) cold damage. If the target is wearing metal armor, it must make a successful DC 17 Constitution saving throw or gain one level of exhaustion.
Freezing Breath (Recharge 5-6). The thuellai exhales an icy blast in a 40-foot cone. Each target in the area takes 39 (6d12) cold damage, or half damage with a successful DC 17 Constitution saving throw.
Algid Aura. All creatures within 10 feet of a thuellai take 7 (2d6) cold damage at the beginning of the thuellai’s turn. Spells or magical effects that protect against cold are affected as if by a dispel magic spell (the theullai’s effective spellcasting bonus is +5) if a thuellai is within 20 feet of the target at the start of the theullai’s turn, and nonmagical flames within 20 feet of the thuellai are extinguished at the start of its turn.
Howl of the Maddening Wind (3/day). A thuellai’s howl can cause creatures to temporarily lose their minds and even to attack themselves or their companions. Each target within 100 feet of the theullai and able to hear the howl must make a successful DC 14 Wisdom saving throw or roll 1d8 and consult the table below at the start of its next turn. An affected creature repeats the saving throw at the end of each of its turns; a success ends the effect on itself, but a failure means it must roll again on the table below at the start of its next turn.
1 - Act normally
2-4 - Do nothing but babble incoherently
5-6 - Do 1d8 damage + Str modifier to self with item in hand
7-8 - Attack nearest target; select randomly if more than one
Blizzard (1/Day). The thuellai creates an icy blizzard in the area around it. A 50-foot radius sphere surrounding the theullai fills with icy fog, whirling snow, and driving ice crystals. Vision is lightly obscured, and creatures have disadvantage on Wisdom (Perception) checks that rely on vision or hearing. The ground in the affected area becomes difficult terrain. The effect lasts for 10 minutes and moves with the theullai.