Multiattack. The dragon makes two claw attacks and one bit attack.

claw. Melee Weapon Attack: +11 to hit, reach 5 ft., # target. Hit: 19 (4d6+ 7) [damage type] damage. 

Bite. MeleeWeapon Attack: +11 to hit, reach 5 ft., 1 target. Hit: 19 (4d6 + 7) piercing  damage + 20 (4d8) acid damage 

Regurgitate (recharge 6). Acid pours from the dragons mouth causing one of the following effects:

Drool A 10 foot square within 5 feet of the dragon becomes covered with acid, a creature that starts its turn in it takes 20 (4d8) acid damage 

Barf. Each creature in a 50 foot line must make a dc 24 dex saving throw or take 30 (5d10) acid damage, or half as much on a success.

Acid ball. The dragon spits a ball  acid at one creature within 30 feet of it, They must make a dc 24 dex save or take 70(10d12) acid damage