Allure of the Icicle

Fey Step (Recharge 4-6). As a bonus action, Allure can teleport up to 30 feet to an unoccupied space she can see.

Innate Spellcasting. Allure's innate spellcasting ability is Intelligence (spell save DC 16). She can innately cast the following spells, requiring no material components:

At will: fog cloud, gust of wind

2/day each: cone of cold, ice storm

Magic Resistance. Allure has advantage on saving throws against spells and other magical effects.

Sorrowful Presence. Any non-fey creature that starts its turn within 60 feet of Allure must make a DC 13 Wisdom saving throw. On a failed save, the creature becomes charmed by Allure for 1 minute. While charmed in this way, the creature has disadvantage on ability checks and saving throws. The charmed creature can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success. If a creature's saving throw is successful or the effect ends for it, the creature is immune to Allure's sorrowful presence for the next 24 hours. Whenever Allure deals damage to the charmed creature, it can repeat the saving throw, ending the effect on itself on a success.

Special Equipment. Allure carries one spell scroll of ice storm and wears a bandersnatch cloak of abjuration.

Longsword. Melee Weapon Attack: +8 to hit, reach 5ft., one target. Hit: 8 (1d8 + 4) slashing damage plus 3 (1d6) cold damage, or 9 (1d10 + 4) slashing damage if used with two hands.
Longbow. Ranged Weapon Attack: +8 to hit, range 150.600 ft., one target. Hit: 4 (1d8) piercing damage plus 3 (1d6) cold damage.

Frigid Rebuke. When Allure takes damage from a creature she can see within 60 feet of her, Allure can force that creature to succeed on a DC 16 Constitution saving throw or take 11 (2d10) cold damage.

Bandersnatch Cloak of Abjuration. When you are dealt damage by an attack which deals magical damage, such as a magical weapon or a spell, you can use their reaction to take half damage instead. When you use this feature, the energy of the attack is absorbed and released in a catastrophic wave. Each creature within a 20 foot radius of you must succeed on a DC 15 Dexterity saving throw. On a failed save, the creature takes thunder damage equal to the damage dealt by the attack that triggered this effect. On a successful save, the creature takes half that damage. 
Once this feature has been used, it can be used again until the next dawn.

Allure can take 3 legendary actions, choosing from the options listed below. Only one legendary action option can be used at a time and only at the end of another creature's turn. Allure regains spent legendary actions at the start of her turn.

Move. Alure moves up to her speed.

Attack. Allure makes one attack with her longsword or longbow.

Arcane Chill (3 Actions). Allure attempts to freeze a creature solid. A target Allure can see within 60 feet of her must succeed on a DC 16 Constitution saving throw. On a failed save, the creature begisn to freeze and is restrained. The target must repeat the saving throw at the end of its next turn. On a success, the effect ends. On a failure, the creature is petrified until freed by the greater restoration spell or other magic.
If a creature's saving throw is successful, or the effect ends for it, the creature is immune to Allure's arcane chill for the next 24 hours.