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

Acid Splash. When the troll takes damage of any type but psychic, each creature within 5 feet of the golem takes 9 (2d8) acid damage.

Berserk. Whenever the golem starts its turn with 60 hit points or fewer, roll a d6. On a 6, the golem goes berserk. On each of its turns while berserk, the golem attacks the nearest creature it can see. If no creature is near enough to move to and attack, the golem attacks an object, with preference for an object smaller than itself. Once the golem goes berserk, it continues to do so until it is destroyed or regains all its hit points.

Corrosive Form. A creature that touches the golem or hits it with a melee attack while within 5 feet of it takes 4 (1d8) acid damage. Any nonmagical weapon made of metal or wood that hits the golem corrodes. After dealing damage, the weapon takes a permanent and cumulative −1 penalty to damage rolls. If its penalty drops to −5, the weapon is destroyed.

Nonmagical ammunition made of metal or wood that hits the golem is destroyed after dealing damage.

The golem can eat through 1-inch-thick, nonmagical wood or metal in 1 round.

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.

Self Damage. Each turn, the golem deals 18 (4d8) acid damage to itself. This trait does not function for one turn after the golem takes thunder damage.

Spider Climb. The golem can climb difficult surfaces, including upside down on ceilings, without needing to make an ability check.

Split Off. If the golem takes more than 10 damage at one time (except for force, radiant, necrotic, and psychic), roll a d20 to determine what happens to it:

1–8: One leg is severed from the golem if it has any legs left.

9–16: One arm is severed from the golem if it has any arms left.

17–20: The golem is decapitated.

A severed part acts on the golem's initiative and has its own action and movement. A severed part has AC 8. It has the same traits (except for this trait), resistances, and immunities as the golem, and has blindsight of 60 ft. Any damage it takes is subtracted from the golem's hit points.

A severed leg can make one slam attack or one pseudopod attack each turn, not both, and has a speed of 10 feet and a climbing speed of 5 feet.

A severed arm has a speed of 10 feet, climbing speed of 5 feet, and can make one slam attack or one pseudopod attack on its turn, not both.

If its head is severed, the golem's body is blinded unless the head can see it. The severed head has a speed of 5 feet and a climbing speed of 5 feet. It can make a pseudopod attack, but only against a target in its space.

The golem's speed is halved if it's missing a leg. If it loses both legs, it has a speed of 10 feet and a climbing speed of 5 feet. After this, the golem's speed does not change, no matter how many other limbs it loses. A lone body can make a slam attack each turn.

Each turn, the golem may move up to its speed. Any of the body parts that enter its space reattach to it.

Multiattack. The golem makes two slam attacks and two pseudopod attacks.

Slam. Melee Weapon Attack: +8 to hit, reach 5 ft., one target. Hit: 16 (2d10 + 5) bludgeoning damage. If the target is a creature, it must succeed on a DC 15 Constitution saving throw or have its hit point maximum reduced by an amount equal to the damage taken. The target dies if this attack reduces its hit point maximum to 0. The reduction lasts until removed by the greater restoration spell or other magic.

Haste (Recharge 5–6). Until the end of its next turn, the golem magically gains a +2 bonus to its AC, has advantage on Dexterity saving throws, and can use its slam attack and pseudopod attack as a bonus action. The golem's speed increases by 10 feet.

Pseudopod. Melee Weapon Attack: +8 to hit, reach 5 ft., one target. Hit: 6 (1d6 + 3) bludgeoning damage plus 18 (4d8) acid damage. In addition, nonmagical armor worn by the target is partly dissolved and takes a permanent and cumulative -1 penalty to the AC it offers. The armor is destroyed if the penalty reduces its AC to 10.