Alacrity. The golem has advantage on Dexterity saving throws. The golem may take an additional action on each of its turns. That action can be used only to take the Dash, Disengage, Hide, or Use an Object action.

Fire Absorption. Whenever the golem is subjected to fire damage, it takes no damage and instead regains a number of hit points equal to the fire damage dealt.

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.

Regeneration. The golem regains 10 hit points at the start of its turn if it has at least 1 hit point.

Multiattack. The golem makes two slam attacks.

Slam. Melee Weapon Attack: +15 to hit, reach 5 ft., one target. Hit: 27 (4d8 + 9) bludgeoning damage.

Poison Breath (Recharge 6). The golem exhales poisonous gas in a 15-foot cone. Each creature in that area must make a DC 19 Constitution saving throw, taking 45 (10d8) poison damage on a failed save, or half as much damage on a successful one.