Tempest Form. The elemental can move through a space as narrow as 1 inch wide without squeezing. A creature that touches the elemental or hits it with a melee attack using a metal weapon takes 9 (2d8) lightning damage. In addition, the elemental can enter a hostile creature's space and stop there. The first time it enters a creature's space on a turn, that creature takes 9 (2d8) lightning damage. A creature that ends its turn inside the elemental's space also takes 9 (2d8) lightning damage.

Grounding. Lightning damage the elemental deals to earth elementals or to creatures that are buried or burrowing in earth is halved.

Magic Weapons. The elemental's weapon attacks are magical.

Tri-Nature. The elemental counts as an elemental of the air, fire, and water sub-types (primary air).

Multiattack. The elemental makes two melee attacks.

Shock. Melee Weapon Attack: +9 to hit, reach 0 ft., one target. Hit: 22 (5d8) lightning damage. This attack is made with advantage against a target wearing metal armor.

Slam. Melee Weapon Attack: +9 to hit, reach 10 ft., one target. Hit: 14 (2d8 + 5) bludgeoning damage plus 4 (1d8) lightning damage and 4 (1d8) thunder damage.

Arc Lightning. The elemental chooses one creature or object within 120 feet and up to three other creatures or objects within 30 feet of the first target. Each target must make a DC 16 Dexterity saving throw. A target takes 28 (8d6) lightning damage on a failed save, or half as much damage on a successful one.

Thunder Pulse. The elemental chooses a direction, then pushes unsecured objects inside its space that aren't being worn or carried 30 feet away in that direction. Each creature in the elemental's space must make a DC 16 Constitution saving throw. On a failed save, a creature takes 14 (2d8 + 5) bludgeoning damage plus 13 (3d8) thunder damage, is knocked prone, and is pushed 30 feet in the same direction.

Vortex (Recharge 5–6). The elemental pulls all unsecured objects within 60 feet of it that aren't being worn or carried 60 feet closer to the center of its space. Each creature within 60 feet of the elemental must make a DC 16 Strength saving throw. On a failed save, a creature takes 27 (5d8 + 5) bludgeoning damage, is knocked prone, and is pulled up to 60 feet toward the center of the elemental's space.