Storm Giant

The giant's innate spellcasting ability is Charisma (spell save DC 17). It can innately cast the following spells, requiring no material components:

At will: detect magic, feather fall, levitate, light

3/day each: control weather, water breathing

The storm giant can breathe air and water.

Melee Weapon Attack: +14 to hit, reach 10 ft.. Hit: 30 (6d6 + 9) slashing damage.

The giant makes two greatsword attacks.

Melee or Ranged Weapon Attack: +14 to hit, reach 5 ft. or range 60/240 ft.. Hit: 35 (4d12 + 9) bludgeoning damage.

The storm giant hurls a magical lightning bolt at a point it can see within 500 ft. of it.
Each creature within 10 feet of that point must make a DC 17 Dexterity saving throw, taking 54 (12d8) lightning damage on a failed save, or half as much damage on a successful one.