Adamantine body. The adamantine golem is immune to critical hits and instead takes normal damage. 

Adamantine strikes. The adamantine golem always critical hits when attacking objects. 

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

Legendary Resistance (2/Day). If the adamantine golem fails a saving throw, it can choose to succeed instead.

Limited Magic Immunity. The Adamantine golem can’t be affected or detected by spells of 6th level or lower unless it wishes to be. It has advantage on saving throws against all other spells and magical effects.

Magic Weapons. The adamantine golem’s weapon attacks are magical.

Multi attack. The adamantine golem makes two slam attacks. 

Slam. Melee Weapon Attack: +17 to hit, reach 10 ft., 1 target. Hit: 65 (10d10 + 10) bludgeoning damage. 

The Adamantine golem can take 2 legendary actions, choosing from the options below. Only one legendary action option can be used at a time and only at the end of another creature’s turn. The Adamantine golem regains spent legendary actions at the start of its turn.

Slam (Costs 1 Actions). The adamantine golem makes one slam attack. 

Stomp (Costs 2 Actions). The adamantine golem stomps making an earthquake within a 100 ft radius of themselves all creature within the radius must make a dc 26 Dexterity saving throw or take 50 (10d10) thunder damage and be knocked prone half as much damage on a failed save.