Death Burst. When the slayer dies, it explodes in a burst of jagged crystal. Each creature within 15 feet of it must make a DC 14 Dexterity saving throw, taking 14 (4d6) slashing damage on a failed save, or half as much damage on a successful one.

Frozen Body. A creature that touches the slayer or hits it with a melee attack within 5 feet of it takes 7 (2d6) cold damage. At the start of the slayer's turn, nonmagical flames within 5 feet of it are extinguished, as well as magical flames created by a spell of 3rd level or lower.

Immutable Form. The slayer is immune to any spell or effect that would alter its form.

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

Multiattack. The slayer makes two attacks, one one of which can be ice ray.

Frostshard. Melee Weapon Attack: +7 to hit, reach 5 ft., one creature. Hit: 9 (2d4 + 4) slashing damage plus 7 (2d6) cold damage.

Ice Ray. Ranged Weapon Attack: +4 to hit, range 60 ft., one creature. Hit: 14 (3d6 + 4) cold damage, and if the target is a creature, it must succeed on a DC 15 Constitution saving throw or gain disadvantage on ability checks and saving throws until the end of the slayer's next turn. A creature that fails the save by 5 or more gains one level of exhaustion.