Dragon, Adamantine (Ancient)

Huge dragon, neutral good

Armor Class 22 (natural armor)

Hit Points 370 (20d20 + 160)

Speed 30 ft., burrow 15ft., fly 40 ft.

28 (9) 12 (1) 27 (9) 14 (2) 16 (3) 14 (2)
  • Saving Throws Dex +8, Con +15, Wis +10, Cha +9

    Skills Athletics +15, Perception +10, Stealth +8

    Damage Resistances fire

    Damage Immunities thunder

    Senses blindsight 30 ft., darkvision 120 ft., passive Perception 14

    Languages Draconic

    Challenge 21 (27,500 XP)

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

    Sunlight Sensitivity. The dragon has disadvantage on attack rolls and on Wisdom (Perception) checks that rely on sight when they, the target of the attack, or whatever they are trying to perceive is in direct sunlight.


    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: +16 to hit, reach 10 ft., one target. Hit: 20 (2d10 + 9) piercing damage.

    Claw.  Melee Weapon Attack: +16 to hit, reach 5 ft., one target. Hit: 18 (2d8 + 9) piercing damage.

    Tail.  Melee Weapon Attack: +16 to hit, reach 15 ft., one target. Hit: 18 (2d8 + 9) piercing 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 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.

    Breath Weapons (Recharge 5-6). The dragon uses one of the following breath weapons.

    Thunder Breath. The dragon exhales a 15-foot cone of sonic energy. Each creature in the area must make a DC 23 Dexterity throw, taking 63 (14d8) thunder damage on a failed save, or half as much damage on a successful one.

    Slowing Breath. The dragon’s breath slows time in a 15-foot cone. Each creature in the area must make a DC 23 Wisdom saving throw or be slowed for 1 minute. A slowed creature’s speed is halved, it takes a -2 penalty to AC and Dexterity saving throws, can’t use reactions, and on its turn it can use either an action or a bonus action, but not both (and cannot make more than one melee or ranged attack during its turn). A creature can repeat the saving throw at the end of each of its turns, ending the effect on a success.

  • Legendary Actions

    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.
    Body Slam (costs 2 actions). The dragon can move 20 feet straight toward a creature. At the end of this movement, each creature within 5 feet of the dragon succeed on a DC 20 Dexterity saving throw or take 18 (2d8 + 9) piercing damage and be knocked prone.

Brutish and short tempered, adamantine dragons are native to the vast cave systems that connect to the Underdark and rarely seen on the surface world.

They have scales the color of blackened iron that protrude like spikes and ruffle like feathers when the dragon is irritated or angry. While stalking their prey an adamantine dragon’s spines fold back tight against its body. Though they can fly like all true dragons, their underground lairs make this normally impractical. More often they fight while firmly planted on the ground, or clinging to cavern walls.

Fiercely Territorial. Adamantine dragons treat their territories like kingdoms, driving off any challengers to their domain and ruling lesser beings as though they were vassals. They demand obedience, but are benevolent masters if they are treated with respect and kept well fed. Adamantine dragons that dwell near the surface often come into conflict with blue dragons who compete for the caverns in which they make their lairs.

Bytopian Dragons. While rare on the prime material worlds, adamantine dragons are more common on the twin paradises of Bytopia. Bytopian adamantine dragons spend significantly more time on the surface world, and therefore do not have the sunlight sensitivity trait.