Clay Golem

Whenever the clay golem is subjected to Acid damage, it takes no damage and instead regains a number of Hit Points equal to the Acid damage dealt.

Whenever the clay golem starts its turn Bloodied, roll 1d6. On a 6, the clay golem goes berserk. On each of its turns while berserk, the clay golem attacks the nearest creature it can see. If no creature is near enough to move to and attack, the clay golem attacks an object. Once the clay golem goes berserk, it remains so until it is destroyed or it is no longer Bloodied.

The clay golem can't shape-shift.

The clay golem has Advantage on saving throws against spells and other magical effects.

The clay golem makes two Slam attacks, or it makes three Slam attacks if it used Hasten this turn.

Melee Weapon Attack: +9 to hit, reach 5 ft.. Hit: 10 (1d10 + 5) bludgeoning plus 6 (1d12) acid damage, and the target's Hit Point maximum decreases by an amount equal to the Acid damage taken.

Recharge 5–6. The clay golem takes the Dash and Disengage actions.