Aetherius

Elemental Magic Resistance. Aetherius has advantage on saving throws against elemental spells and other elemental effects.

Spellcasting. Aetherius is an elemental spellcaster. Her spellcasting ability is Intelligence (spell save DC 17, +9 to hit with spell attacks). Aetherius can cast disguise self at will.

Fire Breath. Ranged Fire Breath (Recharge 2). Aetherius exhales fire in a 30-foot cone. Each creature in that area must make a DC 14 Dexterity saving throw, taking 3(1d6) fire damage on a failed save, or half as much damage on a successful roll

Cold Breath (Recharge 2). The dragon exhales an icy blast in a 30-foot cone. Each creature in that area must make a DC 12 Constitution saving throw, taking 4 (1d8) cold damage on a failed save, or half as much damage on a successful one.

Earthen Grasp You choose a 5-foot-square unoccupied space on the ground that you can see within range. A Medium hand made from compacted soil rises there and reaches for one creature you can see within 5 feet of it. The target must make a Strength saving throw. On a failed save, the target takes 2d4 bludgeoning damage and is restrained for the spell’s duration. As an action, you can cause the hand to crush the restrained target, who must make a Strength saving throw. It takes 2d4 bludgeoning damage on a failed save, or half as much damage on a successful one. To break out, the restrained target can use its action to make a Strength check against your spell save DC. On a success, the target escapes and is no longer restrained by the hand. As an action, you can cause the hand to reach for a different creature or to move to a different unoccupied space within range. The hand releases a restrained target if you do either.

Thunderwave  A wave of thunderous force sweeps out from you. Each creature in a 15-foot cube originating from you must make a Constitution saving throw. On a failed save, a creature takes 2d6 thunder damage and is pushed 10 feet away from you. On a successful save, the creature takes half as much damage and isn't pushed. In addition, unsecured objects that are completely within the area of effect are automatically pushed 10 feet away from you by the spell's effect, and the spell emits a thunderous boom audible out to 300 feet.