Multiattack

The thuellai makes three Icy Claw attacks.

Icy Claw

Melee Weapon Attack: +10 to hit, reach 10 ft., one target. Hit: 15 (2d8 + 6) slashing damage plus 10 (3d6) cold damage.

Freezing Breath (Recharge 5-6)

The thuellai exhales an icy blast in a 60-foot cone. Each creature in the area must make a DC 17 Dexterity saving throw, taking 49 (14d6) cold damage on a failed save, or half as much damage on a successful one.