Ice Devil
Large Fiend (devil), lawful evil
11,500 XP
Special Abilities
Devil's Sight
Magical darkness doesn't impede the devil's darkvision.
Magic Resistance
The devil has advantage on saving throws against spells and other magical effects.
Actions
Multiattack
The devil makes three attacks: one with its bite, one with its claws, and one with its tail.
Bite
Melee Weapon Attack: +10 to hit, reach 5 ft., one target. Hit: 12 (2d6 + 5) piercing damage plus 10 (3d6) cold damage.
Claws
Melee Weapon Attack: +10 to hit, reach 5 ft., one target. Hit: 10 (2d4 + 5) slashing damage plus 10 (3d6) cold damage.
Tail
Melee Weapon Attack: +10 to hit, reach 10 ft., one target. Hit: 12 (2d6 + 5) bludgeoning damage plus 10 (3d6) cold damage.
Wall of Ice
The devil magically forms an opaque wall of ice on a solid surface it can see within 60 feet of it. The wall is 1 foot thick and up to 30 feet long and 10 feet high, or it's a hemispherical dome up to 20 feet in diameter.
When the wall appears, each creature in its space is pushed out of it by the shortest route. The creature chooses which side of the wall to end up on, unless the creature is incapacitated. The creature then makes a DC 17 Dexterity saving throw, taking 35 (10d6) cold damage on a failed save, or half as much damage on a successful one.
The wall lasts for 1 minute or until the devil is incapacitated or dies. The wall can be damaged and breached; each 10-foot section has AC 5, 30 hit points, vulnerability to fire damage, and immunity to acid, cold, necrotic, poison, and psychic damage. If a section is destroyed, it leaves behind a sheet of frigid air in the space the wall occupied. Whenever a creature finishes moving through the frigid air on a turn, willingly or otherwise, the creature must make a DC 17 Constitution saving throw, taking 17 (5d6) cold damage on a failed save, or half as much damage on a successful one. The frigid air dissipates when the rest of the wall vanishes.
Quick Reference
Running This Encounter
Ice Devils are cunning tacticians who prefer ambush and psychological warfare. Set up the encounter with difficult terrain (ice, crevasses) that the devil can navigate but party members struggle with. Use the devil's ability to cast spells and summon allies to control the battlefield. Leverage its high AC and HP by having it maintain distance while minions engage melee combatants.
Combat Tactics
The Ice Devil opens combat with Wall of Ice to separate party members and create cover. It uses its spellcasting (Cone of Cold, Hold Person) from range while summoning lesser devils to engage in melee. When threatened, it attempts to dominate or frighten opponents, then repositions to maintain tactical advantage.
Environment & Setting
A frozen fortress, glacial cavern, or blizzard-swept mountain peak provides ideal terrain. Crevasses, ice pillars, and slippery surfaces offer the devil natural advantages while challenging the party.