Legendary Resistance (3/Day). If the dragon fails a saving throw, it can choose to succeed instead.
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: +11 to hit, reach 10 ft., one target. Hit: 17 (2d10 + 6) piercing damage.
Claw. Melee Weapon Attack: +11 to hit, reach 5 ft., one target. Hit: 13 (2d6 + 6) slashing damage.
Tail. Melee Weapon Attack: +11 to hit, reach 15 ft., one target. Hit: 15 (2d8 + 6) 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 16 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.
Internal Repair Mechanisms. Once per day, when the dragon is below half hitpoints, it can use its internal repair mechanims to bolster its vitality, granting it 100 hit points.
Breath Weapon (Recharge 5–6). The dragon uses its breath weapon.
Force Breath. The dragon exhales raw, arcane magic in a 60-foot cone. Each creature in that area must make a DC 18 Constitution saving throw, taking 45 (13d6) force damage on a failed save, or half as much damage on a successful one. Creatures that fail their saved are pushed back 10ft and knock prone.
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 19 Dexterity saving throw or take 13 (2d6 + 6) bludgeoning damage and be knocked prone. The dragon can then fly up to half its flying speed.
Description
A massive construct, four armored, clawed feet menacingly digging into the stonework, cracking the floor beneath it. Giant, iron wings beat the air and send rippling waves of pressure at you, blowing back your clothes and sending dust and small stones flying into the air. A single, mighty tail trails behind it, with chain-like linkages between tail segments. As you size up the creature, its chassis is formed from a metallic, skeletal framework, the exterior featuring composite plates on the less mobile portions of the body. Visible from between the armored plating are wooden, root-like cords that make up the flexible musculature of this gigantic, warforged dragon. From the horned crown of its draconic, iron visage, two cruel, sapphire eyes stare back at you as its jaw clicks and unhinges, blue arcane energy crackling from within its maw and gill-like vents around its throat as the construct rears its head back and releases powerful roar.