Amphibious: The dragon can breathe air and water.
Bite. Melee Weapon Attack: +4 to hit, reach 5 ft., one target. Hit: (1d10 + 2) piercing damage plus (1d6) lightning damage.
Lightning Breath (Recharge 5-6). The dragon exhales lightning in a 30-foot line that is 5 feet wide. Each creature in that area must make a DC 11 Constitution saving throw, taking 21 (6d6) lightning damage on a failed save, or half as much damage on a successful one.