Multiattack

The dragon attacks with its bite and twice with its claws. In place of its bite it can use Lightning Pulse.

Bite

Melee Weapon Attack: +16 to hit, reach 15 ft., one target. Hit: 31 (4d10 + 9) piercing damage plus 9 (2d8) lightning damage.

Claws

Melee Weapon Attack: +16 to hit, reach 10 ft., one target. Hit: 22 (3d8 + 9) slashing damage.

Tail

Melee Weapon Attack: +16 to hit, reach 20 ft., one target. Hit: 22 (3d8 + 9) bludgeoning damage and the dragon pushes the target 10 feet away.

Trident (Humanoid Form Only)

Melee or Ranged Weapon Attack: +16 to hit, reach 5 ft. or range 20/60 ft., one target. Hit: 12 (1d6 + 9) piercing damage.

Lightning Pulse

The dragon targets one creature within 60 feet forcing it to make a DC 23 Dexterity saving throw. The creature takes 22 (4d10) lightning damage on a failure or half damage on a success. If the initial target is touching a body of water all other creatures within 20 feet of it and touching the same body of water must also make the saving throw against this damage.

Breath Weapons (Recharge 5-6)

The dragon uses one of the following breath weapons:

Lightning Breath

The dragon exhales lightning in a 120-foot-long 10-foot-wide line. Each creature in the area makes a DC 23 Dexterity saving throw taking 93 (16d10) lightning damage on a failed save or half damage on a success. A creature that fails the saving throw can't take reactions until the end of its next turn.

Ocean Surge

The dragon exhales a torrent of seawater in a 30-foot cone. Each creature in the area makes a DC 23 Strength saving throw. A creature that fails is pushed 40 feet away from the dragon and knocked prone while one that succeeds is pushed only 20 feet away and isnt knocked prone.