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

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

Magic Weapons. The golem's weapon attacks are magical.

Multiattack. The golem makes two slam attacks.

Slam. Melee Weapon Attack: +10 to hit, reach 5 ft., one target. Hit:19 (3d8 + 6) bludgeoning damage.

Slow (Recharge 5–6). The golem targets one or more creatures it can see within 10 feet of it. Each target must make a DC 17 Wisdom saving throw against this magic. On a failed save, a target can't use reactions, its speed is halved, and it can't make more than one attack on its turn. In addition, the target can take either an action or a bonus action on its turn, not both. These effects last for 1 minute. A target can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success.

Sapphire. The sapphire has 3 charges. As an action, the golem can expend 1 charge to cast dispel magic (as a 9th-level spell) from the sapphire using Constitution as its spellcasting ability. The sapphire ceases to glow if all its charges are expended, but it regains 1d3 expended charges daily at dawn and glows again once it has 1 or more charges.