Acidic healing. When hit with a acid attack it is immune and heals the damage it would have taken if it was not immune to the acid attack (if it is at max HP or if the heal makes it at max HP and there is still more acid damage to heal it gains temporary HP equal to the rest of the damage)

Acid Weapons. Any metal melee weapon the acid slime wields after grappling a creature deals an extra 20 (5d6) Acid damage on a hit it gains the weapon attack of someone it grappled.

Acid Body. A creature that touches the acid slime or hits it with a melee attack while within 5 feet of it takes 20 (4d10) acid damage.

Multiattack. The acid slime can make two attacks one with it's acid slime spear and one with it's acid slime ball.

Acid slime spear. Acid slime spear: +8 to hit, reach 20 ft., 1 target. Hit: 30 (5d8 + 5) acid damage. 

Acid slime ball. Acid slime ball: +8 to hit, range 30/60 ft., 4 target. Hit: 25 (5d12+ 5) acid damage.

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Acid grapple. When hit with a melee attack the acid slime will try to grapple you make a dc 14 strength check if fail you are grappled and take acid body effect if success you are not grappled.

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Legendary Action Name (Costs # Actions). Enter the description for your legendary action.

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Mythic Action Name (Costs # Actions). Enter the description for your mythic action.