These are sorted by the time in which they appear in BTACD's history.
The dark ones
Gorganoth
Role;; first King of Serpents creator of the snakekind and the shriekans.
Known Abilities;; Hypnotic control; exceptionally strong venom; ruthlessness personified.
Known History;; The Lord of the Desert in Millirand, Gorganoth wanted it all - he aspired to become one of the gods. He created his own species, crafted the desert to his liking, and released the naga, snakekind and shriekans upon the Realm. At last, his dark reign - including the destruction of Millirand's first Ether - ended by the claws of Arrowhead's dragonkin, at the cost of a young royal's life.
Snayc
Role;; Father of Snakra; King of the Snakekind. Born enemy of the dragons of Millirand and Felnova and sought to unseat them from their rule.
Known Abilities;; Deadly poisonous bite that has no cure; limited reiatsu; vast control over legions of enemies such as shriekans, sarka, dreameaters, vampires and undead. Also could utilize shadow magic in any way imaginable - once called Lord of Darkness, under the thrall of Dhath.
Known History;; First hatched in Millirand as a result of Gorganoth's cunning, Snayc reigned long as the serpentkin's greatest king. He, along with his daughter, sought to destroy the dragons of Ki-Lia, but were unsuccessful. Unfortunately, he returned to attack Felnova and Evylon, Snakra at his side. He was destroyed by Kazule, who obliterated the darkness within his soul, and his spirit now rests peacefully in the Soulplane.
Snakra
Role;; Queen of Snakekind, original Enslaver of the dragons alongside her father in a time before the birth of Queen Verridith. Lived as a terror upon the land during Millirand's earliest days.
Known Abilities;; Deadly poisonous bite; able to bypass nearly all mental defenses; supreme control over all natural enemies of the dragons.
Known History;; As Queen of the Snakekind, she ruled for a time in Vystriana before being unseated by Fang, Verridith and the free races. Although believed to be dead, she has arisen out of nightmares to make bids for her lost power, and lives vicariously through her brother, Orochi.
Thief
Role;; A thief branded as a traitor among his Vystrian kin; Verridith's first enemy, in the first days of her rule.
Known Abilities;; Cleverness, stealth, and deceit.
Known History;; Not much is known but that this master thief was one of the Ruby Faction, and had stolen the entire treasure of a great Red named Solarius. Verridith and a small group of dragons found him and put him to justice many years ago.
Deathwing
Role;; Creator of Destruction, King of Shadowdrakes, Lord of Flame.
Known Abilities;; A masterful utilization of fire and flame, as well as an uncanny control over the darkness in one's heart. Able to master the heat of anything and multiply it by the thousands, resulting in instant death.
Known History;; Arisen from a Realm born of fire and waste, Deathwing forsook his former name and came to Vystriana hoping for conquest. Though he and his allies brought destruction upon Vystriana, he was utterly defeated by the dragons of that Realm.
Cal-Cia/Nuar
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Frog King
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The Empress
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Arigonos
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Drakaras
Role;; A sorcerer-dragon in supreme control of Shadowmagic; led a legion of traitor dragons against Vystriana.
Known Abilities;; Able to possess and command shadows to his bidding; often killed by stealing a creatures shadow and using it to suffocate the enemy. Able to slip into nightmares and instill madness.
Known History;; After gathering a succession of traitors, Drakaras launched a vicious campaign against Vystrianna, killing many and leaving a legacy of terror behind. The exact details of his brief reign are lost, but the taint of his power remains. He gained at the time the name of 'Serpenthunter', and tale of it lives today. It is said that Rune the Shadowking took over his powers and resides in the Valley of Godshome.
Zacyn
Role;; Traitorous member of the Five; corrupted by his greed, he turned on Felnova and began wreaking havoc.
Known Abilities;; Control over the cosmos, sun and moon; able to change size at will; immense draw on reiatsu; able to tap into the Ether Felnova.
Known History;;
Zacyn turned on Felnova and began targeting the creatures upon it, causing terrific horrors to the people of the Realms. The Dark Five seeded themselves throughout the traitor Gods servants and it took the combined power of the remaining Four and the Ethers to destroy Zacyn and stabilize the world. A new God, Lyfe, arose to take his place among the Five.
An and Ima
Role;; Ancient creatures believed to have been made by Leartes, possessed by a terrible desire to destroy every living thing. Contained within the being of Repentance.
Known Abilities;; An is capable of vicious mental attacks as well as an icy breath, complimented by physical strength; Ima is possessed of an acidic saliva, poison-tipped spikes and a scream similar to that of Shriekans.
Known History;; Awoke due to the instability raging across Felnova and proceeded to wreak a path of destruction until eventually stopped by the demon Solan. Rather than perish, recombined into the being Repentance. Believed to be immortal, at least in terms of a natural death.
Kirai
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Kairn
Role;; A necromancer able to summon the dead and give them corporeal form, bound to servitude. These souls were known as Hunters. Sought to destroy all Realms and create a 'perfect' Realm in his image.
Known Abilities;; Complete control over Hell and its minions; able to summon and raise the dead; was an archmage and a dragon, though secretly, and quite powerful in all workings of magic.
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Chamenos
Role;; King of Kurai after ursurping the Silver Throne. Began a conquest of the Realms.
Known Abilities;; Black blood; Tri'akun; unsurpassed reiatsu strength; royal demonic heritage.
Known History;; Believed to be the twin soul of Solaerion Fallenskye, the brother of Aeirs Bloodreign and second in line for the throne. Manifested and divided himself from Solan, trapping his other half inside a Soulgem, and proceeded a ruthless takeover of the Demon Realm. Succeeded in crushing every Realm save Felnova and causing serious damage to the Markers. Was eventually crushed under the collapse of his growing empire; disappeared along with all traces of the original War family.