Multiattack

The dragon can use its Aura of Madness. It then makes three attacks: one with its bite and two with its claws.

Bite

Melee Weapon Attack: +12 to hit, reach 10 ft., one target. Hit: 18 (2d10 + 7) piercing damage plus 7 (2d6) cold damage.

Claw

Melee Weapon Attack: +12 to hit, reach 5 ft., one target. Hit: 14 (2d6 + 7) slashing damage plus 3 (1d6) cold damage.

Tail

Melee Weapon Attack: +12 to hit, reach 15 ft., one target. Hit: 16 (2d8 + 7) bludgeoning damage.

Aura of Madness

As ancient void dragon, with DC 18 Wisdom saving throw.

Breath Weapons (Recharge 5-6)

The dragon uses one of the following breath weapons:

Gravitic Breath

The dragon exhales a 60-foot cube of powerful localized gravity, originating from the dragon. Falling damage in the area increases to 1d10 per 10 feet fallen. When a creature starts its turn within the area or enters it for the first time in a turn, including when the dragon creates the field, must make a DC 20 Dexterity saving throw. On a failure the creature is restrained. On a success the creature's speed is halved as long as it remains in the field. A restrained creature repeats the saving throw at the end of its turn. The field persists until the dragon's breath recharges, and it can't use gravitic breath twice consecutively.

Stellar Flare Breath

The dragon exhales star fire in a 60- foot cone. Each creature in that area must make a DC 20 Dexterity saving throw, taking 31 (9d6) fire damage and 31 (9d6) radiant damage on a failed save, or half as much damage on a successful one.

Teleport

The dragon magically teleports to any open space within 100 feet.