Legendary Resistance (3/Day). If the dragon fails a saving throw, it can choose to succeed instead.

Unusual Nature. The dragon does not need food, water or air to live. Additionally, when in contact with any kind of metal, the dragon can cast Mending on itself to regain 3d8 hit points, consuming the metal it was in contact with. It requires 3 pounds of metal to do so.

Multiattack. The dragon can use its Frightful Presence. It then makes three attacks: one with its bite and two with its claws.

Bite. Melee Weapon Attack: +13 to hit, reach 10 ft., one target. Hit: 18 (2d10 + 7) piercing damage plus 7 (2d6) radiant damage.

Claw. Melee Weapon Attack: +13 to hit, reach 5 ft., one target. Hit: 14 (2d6 + 7) slashing damage.

Tail. Melee Weapon Attack: +13 to hit, reach 15 ft., one target. Hit: 16 (2d8 + 7) bludgeoning damage.

Frightful Presence. Each creature of the dragon’s choice that is within 120 feet of the dragon and aware of it must succeed on a DC 19 Wisdom saving throw or become frightened for 1 minute. A creature can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success. If a creature’s saving throw is successful or the effect ends for it, the creature is immune to the dragon’s Frightful Presence for the next 24 hours.

Laser Barrage (Recharge 5–6). The dragon shoots small beams of lasers in a 60-foot cone. Each creature in that area must make a DC 21 Dexterity saving throw, taking 63 (18d6) radiant damage on a failed save, or half as much damage on a successful one.

Shape the Future. When a creature within 30 ft. of the dragon makes an ability check, attack roll or saving throw, the dragon can choose to replace the result of the d20 with 10 before it is rolled. It can use this reaction only once per day.

The 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 dragon regains spent legendary actions at the start of its turn.

Detect. The dragon makes a Wisdom (Perception) check.

Tail Attack. The dragon makes a tail attack.

Wing Attack (Costs 2 Actions). The dragon beats its wings. Each creature within 10 feet of the dragon must succeed on a DC 22 Dexterity saving throw or take 15 (2d6 + 8) bludgeoning damage and be knocked prone. The dragon can then fly up to half its flying speed.