Maelrith, Queen of the Unthawed Court

Traits

• Legendary Resistance (3/Day). If Maelrith fails a saving throw, she can choose to succeed instead.
• Magic Resistance. Maelrith has advantage on saving throws against spells and other magical effects.
• Mantle of the Unthawed. The ground within 30 feet of Maelrith is difficult terrain for her enemies. A creature that starts its turn in that area takes 10 (3d6) cold damage, and fire in the area burns only half as bright.
• Oath-Bound. Maelrith can't break a promise she has spoken aloud. If she is forced to, she takes 55 (10d10) psychic damage and loses her Legendary Resistance until the next winter solstice.

Spellcasting

Maelrith, Queen of the Unthawed Court is a 20th-level spellcaster. Their spellcasting ability is Charisma (spell save DC 23, +15 to hit with spell attacks).

• Cantrips (at will). Mage Hand, Minor Illusion, Ray of Frost
• 1st level (4 slots). Charm Person, Fog Cloud
• 2nd level (3 slots). Hold Person, Misty Step
• 3rd level (3 slots). Counterspell, Sleet Storm
• 4th level (3 slots). Dimension Door, Ice Storm
• 5th level (3 slots). Cone of Cold, Hold Monster
• 6th level (1 slot). Otiluke's Freezing Sphere
• 7th level (1 slot). Plane Shift
• 8th level (1 slot). Dominate Monster
• 9th level (1 slot). Weird

Actions

• Multiattack. Maelrith makes three Frostbrand Rapier attacks. She can replace one of these attacks with a Heartfrost Glance.
• Frostbrand Rapier. Melee Weapon Attack: +12 to hit, reach 5 ft., one target. Hit: 14 (2d8 + 5) piercing damage plus 22 (5d8) cold damage. A creature hit by this attack can't take reactions until the start of its next turn as frost laces through its joints.
• Heartfrost Glance. Ranged Weapon Attack: +15 to hit, range 120 ft., one target. Hit: 41 (6d10 + 8) cold damage. A shard of blue light leaps from the Queen's crown to the target's chest.
• The Long Winter (Recharge 5-6). Maelrith exhales the breath of a winter that never ended, filling a 90-foot cone with killing frost and the silence of a buried court. Each creature in the area must make a DC 23 Constitution saving throw, taking 72 (16d8) cold damage on a failed save, or half as much damage on a successful one. On a failed save, a creature is also restrained. A creature can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success.

Bonus Actions

• Snowfall Step. Maelrith dissolves into a flurry of snow and reappears in an unoccupied space she can see within 60 feet.

Reactions

• Mirror of Rime. Trigger: Maelrith is hit by an attack she can see. A pane of ice forms between Maelrith and the blow, adding 5 to her AC against that attack. If the attack then misses, the attacker takes 13 (3d8) cold damage from the shattering pane.

Legendary Actions

Maelrith, Queen of the Unthawed Court 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. Maelrith regains spent legendary actions at the start of their turn.

• Rapier. Maelrith makes one Frostbrand Rapier attack.
• Snowfall Step. Maelrith uses Snowfall Step.
• Command of the Court (Costs 2 Actions). Each creature of Maelrith's choice within 60 feet that can hear her must succeed on a DC 23 Wisdom saving throw or use its reaction to move up to its speed in a direction she chooses. A creature that fails by 5 or more also falls prone.
• Winter's Verdict (Costs 3 Actions). Maelrith casts a spell of 5th level or lower from her list, expending a spell slot as normal.

Lair Actions

• Frozen Portraits. The ice-bound courtiers lining the throne room walls open their eyes and stare at the intruders until initiative count 20 on the next round. Each creature in the area must make a DC 15 Wisdom saving throw. On a failed save, a creature is frightened.
• Black Ice. Ice spreads across the floor in a 20-foot square Maelrith can see within 120 feet. The area is difficult terrain until initiative count 20 on the next round, and each creature on it when it forms must succeed on a DC 15 Dexterity saving throw or fall prone.
• Hailstorm. Hail hammers down in a 20-foot-radius, 40-foot-high cylinder centered on a point Maelrith can see. Each creature in the cylinder must make a DC 15 Dexterity saving throw, taking 14 (4d6) bludgeoning damage on a failed save, or half as much on a success.

Regional Effects

• Endless Snow. Snow falls within 6 miles of the lair in every season. Rivers freeze solid, and summer never arrives; crops planted in the region fail.
• Frozen Faces. Humanoids who sleep within 6 miles of the lair dream of a glittering ballroom and wake unable to feel warmth. Such a creature has disadvantage on saving throws against being charmed by fey until it spends a night more than 6 miles away.
• Paths of Frost. Within 1 mile of the lair, frozen footpaths appear overnight and lead travellers in slow circles back toward Maelrith's palace.