Kigatiir, Voidmarked

Actions

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) 2d10+6 piercing damage plus 4 (1d8) 1d8 acid damage.
Claw. Melee Weapon Attack: +11 to hit, reach 5 ft., one target. Hit: 13 (2d6 + 6) 2d10+6 slashing damage.
Tail. Melee Weapon Attack: +11 to hit, reach 15 ft., one target. Hit: 15 (2d8 + 6) 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.
  Acid Breath (Recharge 5–6). The dragon exhales acid in a 60-foot line that is 5 feet wide. Each creature in that line must make a DC 18 Dexterity saving throw, taking 54 (12d8) acid damage on a failed save, or half as much damage on a successful one.

Legendary Actions

Kigatiir can take 3 legendary actions, choosing from the options below. Only one legendary action can be used at a time and only at the end of another creature's turn. Kigatiir 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). Kigatiir beats his wings. Each creature within 10 feet of the dragon must succeed on a DC 19 Dexterity saving throw or take 13 (2d6 + 6) 2d6+6 bludgeoning damage and be knocked prone. Kigatiir can then fly up to half his flying speed.
  Invocation of The Void (Costs 1 Action). Kigatiir draws upon the energy left on him by the Voidmark, causing shadowy tendrils lash out at all hostile creatures within 60 feet. All targets must succeed on a DC 19 Constitution saving throw or take 12 (2d12) necrotic damage on a failed save, or half as much on a successful one. Kigatiir can only take this legendary action while he is on the ground.

Lair Actions

On initiative count 20 (losing initiative ties), the dragon takes a lair action to cause one of the following effects; the dragon can't use the same effect two rounds in a row:
  Pools of water that the dragon can see within 120 feet of it surge outward in a grasping tide. Any creature on the ground within 20 feet of such a pool must succeed on a DC 15 Strength saving throw or be pulled up to 20 feet into the water and knocked prone.
A cloud of swarming insects fills a 20-foot-radius sphere centered on a point the dragon chooses within 120 feet of it. The cloud spreads around corners and remains until the dragon dismisses it as an action, uses this lair action again, or dies. The cloud is lightly obscured. Any creature in the cloud when it appears must make on a DC 15 Constitution saving throw, taking 10 (3d6) 3d6 piercing damage on a failed save, or half as much damage on a successful one. A creature that ends its turn in the cloud takes 10 (3d6) 3d6 piercing damage.
Magical darkness spreads from a point the dragon chooses within 60 feet of it, filling a 15-foot-radius sphere until the dragon dismisses it as an action, uses this lair action again, or dies. The darkness spreads around corners. A creature with darkvision can't see through this darkness, and nonmagical light can't illuminate it. If any of the effect's area overlaps with an area of light created by a spell of 2nd level or lower, the spell that created the light is dispelled.

Appearance. Carrying the vestiges of his black chromatic ancestry, the mark of Xysval has shifted Kigatiir into a shell of his former self. Searing, open wounds cover the dragon's body, all leaking a sickly green flame reminiscent of the worst mutated by the Greywalker's Blight. His voice is croaky, yet rattles throughout Gurhudd Peak clearly, regardless of which cavern one would be stood in.
History. Exiled from his homeland of Maegra, Kigatiir was spurned by the Chromatic race for the pact he made with a being from the Far Realm known as Xysval. Fleeing to Juddulhon, he found sanctuary within Gurhudd peak. It was there that he began experimenting with things found in the Underdark, eventually creating the disease known as the Greywalker's Blight.
Roleplay Information. Kigatiir's mind has been twisted and corrupted by the void, seeking to aid in its consumption of all things by any means possible. Despite the power he has been gifted, though, he still knows that his bretheren can hunt him down at any time so he hides within the vast caverns weaving through Gurhudd Peak, often secluding himself within the mountain spring at the very top of the mountain while leaving his creations to roam free throughout the Badlands. Unlike other Chromatics, he is cowardly and fears death to a degree that drove him into the pact with Olsurvan, that drive continuing his plight of experimentation on mortal beings.