Chain Golem

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.

 Charming Appearance.  As a bonus action on each of the golems turn it can make a creature with in 30ft of it make a DC 18 Wisdom saving throw or be charmed. 

Multiattack. The golem makes three melee attacks.

Chain. Melee Weapon Attack: +13 to hit, reach 5 ft., one target. Hit: 20 (3d8 + 7) slashing damage the target must succeed a DC 20 Strength check or be grappled. 

Whispers of the Chain (Recharge 5-6). The golem exhales poisonous gas in a 15-foot cone. Each creature in that area must make a DC 19 Wisdom saving throw, taking 45 (10d8) physic damage on a failed save, or half as much damage on a successful one.