Alysm

Berserk. Whenever Alysm starts its turn with 25 hit points or fewer, roll a d6. On a 6, Alysm goes berserk. On each of its turns while berserk, Alysm attacks the nearest creature it can see. If no creature is near enough to move to and attack, Alysm attacks an object, with preference for an object smaller than itself. Once Alysm goes berserk, it continues to do so until it is destroyed or regains all its hit points.

Hiraeth, if within 60 feet of the berserk Alysm, can try to calm it by speaking firmly and persuasively. Alysm must be able to hear Hiraeth, who must take an action to make a DC 15 Charisma (Persuasion) check. If the check succeeds, Alysm ceases being berserk. If it takes damage while still at 40 hit points or fewer, Alysm might go berserk again.

Aversion of Fire. If Alysm takes fire damage, it has disadvantage on attack rolls and ability checks until the end of its next turn.

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

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

Magic Weapons. Alysm's weapon attacks are magical.

Multiattack. The golem makes two slam attacks.

Slam. Melee Weapon Attack: +7 to hit, reach 5 ft., one target. Hit: 13 (2d8 + 4) bludgeoning damage.

Bite. Melee Weapon Attack: +5 to hit, reach 5 ft., one target. Hit: 10 (2d6 + 3) piercing damage. If the target is a creature, it must succeed on a DC 13 Strength saving throw or be knocked prone.

Hooves. Melee Weapon Attack: +6 to hit, reach 5 ft., one target. Hit: 11 (2d6 + 4) bludgeoning damage.