Large Construct, Unaligned
Armor Class 19 (natural armor)
Hit Points 210 (20d10 + 100)
Speed 30 ft.
STR
24 (+7)
DEX
9 (-1)
CON
20 (+5)
INT
5 (-3)
WIS
11 (+0)
CHA
5 (-3)
Saving Throws STR +12, CON +10
Damage Vulnerabilities Thunder
Damage Immunities Fire, Poison, Psychic; Bludgeoning, Piercing, and Slashing from Nonmagical Attacks that aren't Adamantine
Senses Darkvision 120 ft., Tremorsense 60 ft., Passive Perception 10
Languages Terran , understands but cannot speak
Challenge 14 (11,500 XP)
Proficiency Bonus +5
Traits

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.
Siege Monster. The golem deals double damage to objects and structures.

 
Actions

Multiattack. The golem makes two melee attacks.
Slam. Melee Weapon Attack: +12 to hit, reach 5 ft., one target. Hit: 20 (3d8 + 7) bludgeoning damage.
Crystal Shards (Recharge 6). The golem unleashes shards of amethyst crystal in a 15-foot cone. Each creature in that area must make a DC 18 Dexterity saving throw, taking 36 (8d8) slashing damage on a failed save, or half as much damage on a successful one.

Firespix