Adult Void Dragon

Chill of the Void. Cold damage dealt by the Void Dragon ignores resistance to cold damage, but not cold immunity.

Void Dweller. The Void Dragon does not require air, food, drink, or sleep.

Multiattack. The Void 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: +10 to hit, reach 10 ft., one target. Hit: 15 (2d10 + 5) piercing damage plus 7 (2d6) cold damage.

Claw. Melee Weapon Attack: +10 to hit, reach 5 ft., one target. Hit: 12 (2d6 + 5) slashing damage plus 3 (1d6) cold damage.

Tail. Melee Weapon Attack: +10 to hit, reach 15 ft., one target. Hit: 14 (2d8 + 5) bludgeoning damage.

Aura of Madness. Each creature of the Void Dragon's choice that is within 60 feet of it and aware of it must succeed on a DC 15 Wisdom saving throw or become frightened for 1 minute. A creature repeats the saving throw at the end of each of its turns, ending the effect on a success. If a creature's saving throw is successful or the effect ends for it, the creature is immune to the Void Dragon's Aura of Madness for the next 24 hours.

Stellar Flare Breath (Recharge 5-6). The Void Dragon exhales star fire in a 60-foot cone. Each creature in that area must make a DC 17 Dexterity saving throw, taking 21 fire damage on a failed save, or half as much damage on a successful one.

Teleport. The Void Dragon magically teleports to any open space within 100 feet.

Void Twist. When the Void Dragon is hit by a ranged attack, it can create a small rift in space to increase its AC by 2 against that attack. If the attack misses because of this increase, the Void Dragon can choose a creature within 30 feet to become the new target for that attack. Use the original attack roll to determine if the attack hits the new target.

The Void Dragon can take 3 legendary actions, choosing from the options below. Only one legendary action option can be used at a time and only at the end of another creature's turn. The Void Dragon regains spent legendary actions at the start of its turn.

Detect. The Void Dragon makes a Wisdom (Perception) check.

Tail Attack. The Void Dragon makes a tail attack.

Void Slip (Costs 2 Actions). The Void Dragon twists the fabric of space. Each creature within 15 feet of the dragon must succeed on a DC 16 Dexterity saving throw or take 12 (2d6 + 5) bludgeoning damage and be knocked prone. The dragon can then teleport to an unoccupied space within 40 feet.