Acid Absorption. If the creature Is subject to acid damage it takes no damage and instead regains hit points equal to the damage dealt

Explosion of Death. Upon dropping to zero hit points the Junk explodes. Any creature within 30 ft must succeed on a DC 15 dexterity saving throw, taking 5d10 acid damage on a failure or half as much on a success.

Multi Attack. The Junk can make two attacks, one with it's Fist and another with it's Acid bomb

Fist. Melee Weapon Attack: +8 to hit, reach 10 ft., 1 target. Hit: 18 (4d6 + 6) [Acid] damage.

Acid bomb. Ranged Weapon Attack: Recharge 5-6: The creature points a giant fist at an object/creature within 60ft. The fist shoots of it's arm and explodes at that point. Any creature within 25ft, must succeed on a DC 18 Dexterity check or take 5d10 acid damage on a failure or half as much on a success.

Acid Attack. The Junk throws it's Fist when attacked, the attack has a +8 to hit, reach 5 ft., 1 target. Hit: 12 (2d6+ 6) [acid] damage