Despite multiple copies of her card existing, as discussed in this headcanon, Red-Eyes is the only one of her kind. She has taken many forms throughout the centuries and her spirit inhabits several cards; humanity has come to view them as separate monsters, but all have been her.
The Black of Legend is the egg form of Red-Eyes. A touch of her aura lingers within this, enough to render it linked to her, but it is not a Duel Spirit, nor is it living. Black Dragon’s Chick is the newborn form, holding her spirit where the Black of Legend holds none. Red-Eyes Baby Dragon is her child form, as much her as her true form, and has her spirit as much as Black Dragon’s Chick.
Red-Eyes Black Metal Dragon is an upgraded variant of her original form, unlocked through the use of Metalization - Magic-Reflection Armour. This spirit of this form is still Red-Eyes, albeit with an altered physical appearance. She cannot ascend into this form without the use of Magic-Reflection Armour.
Sin Red-Eyes Black Dragon is a corrupted form given to her when she is stolen by Paradox’s future technology. Her anger and temper are exacerbated and multiplied tenfold, with the dragon becoming little more than a mindless raging beast. Any speech, rare though it will be given her intense bestial nature, will be garbled and fraught with snarls, almost unintelligible for sounds of fury. Though she will pretend otherwise, Red-Eyes remembers every moment she spent in this form under Paradox’s control.
Red-Eyes Darkness Dragon, as with Red-Eyes Black Metal Dragon, is an upgraded form for Red-Eyes, rather than an entirely different monster. It still holds her spirit as an extension of Red-Eyes and can be accessed with intense concentration and willpower.
Red-Eyes Darkness Metal Dragon is another form available to Red-Eyes, accessible only with the will of the duelist and the support of her retainers. Whereas Red-Eyes Darkness Dragon is thought of as a trump card, an ace up her proverbial sleeve to prove Red-Eyes is just as mighty as Blue-Eyes, Red-Eyes Darkness Metal Dragon is thought on in neutral terms. It is not a form often accessed, used most often at the hands of Darkness, and so has little meaning to Red-Eyes.
Red-Eyes Flare Metal Dragon is not achieved solely through Red-Eyes’ power nor her duelist’s will, but through working in tandem with other monsters. It is not a form Red-Eyes has achieved as it requires willingly working alongside others, something she wholly avoids and despises. Although she is not aware of this fact, she could achieve this form by working in complete synchronicity with Red-Eyes Black Dragon Sword as it is a manifestation of her power gifted by Hermos. Any Duelist that forces her to assume this form by forcibly overlaying her with another Level 7 monster becomes immediately detestable in Red-Eyes’ mind and would likely wake to find Red-Eyes removed from their deck the next day.
Red-Eyes Slash Dragon, on the other hand, is a form that has been achieved a handful of times, often with Red-Eyes Metal Knight Gearfried. Red-Eyes’ dislike of working with others affects this form as to why it has not been accessed more, but she is not foolish enough to allow her pride to get in the way of her survival. She will assume this form only in the direst of circumstances; although it can be achieved with all Warrior-types, her preferred fusion partner, if it is called for, is Red-Eyes Metal Knight Gearfried. She can fuse with Metal Knight Gearfried, but by far prefers the other fusion monster to come from her own archetype.
Red-Eyes Undead Dragon is another alternate form, unlocked this time by her death. Red-Eyes can become this dragon with great concentration and exertion, or at the behest of her duelist, but will transcend permanently into this form at the time of her death. It is possible to restore her to life and her own true form through the power of Hermos and Red-Eyes Spirit, though Red-Eyes herself does not know this. She will not willingly assume this form unless faced with the certainty she will be killed otherwise as she believes it to be a permanent transmutation. She does not know she will become this on death.
Meteor Black Dragon, the Comet Dragon is a form achieved by Red-Eyes fusing with her most favoured retainer, Red-Eyes Doomstar Dragon - Meteor Dragon. It can be achieved using other Level 6 Dragon-types, but Doomstar Dragon is by far her most preferred fusion partner. Although she dislikes working with and relying on others, this is a form she will more willingly assume, calling forth Doomstar Dragon in order to fuse with them and prove the might of the Red-Eyes archetype.
Black Daemons Dragon as a fusion-based form is known to Red-Eyes, but has never been achieved by her of her own free will. She sees Summoned Daemon as far beneath her, despite it having 100 more ATK than her, and so treats any form assumed by fusing with it with disdain. Jounouchi is subject to her scorn for using this form so often where she believes it possible for her to win the duel by her own means and potential.
Meteor Black Dragon is the last of the forms available to Red-Eyes and is the second to be unknown to her. Like Summoned Daemon, Meteor Dragon is thought of as a lesser being, existing on the fringes of her awareness as a monster thought wrongly by humanity to be connected to her and permitted only to exist on the fringes of her territory. Were she forced to assume this form by a duelist, she would appreciate and be subtly impressed by her increase in ATK, and would not disdain this form as much as she does Black Daemons Dragon.
As with the Signer Dragons and other dragons of legend, Red-Eyes has servants and retainers within her archetype. In the human world, these have become support cards and monsters for the Red-Eyes archetype, but in the spirit world they exist to serve Red-Eyes, often shaped by her power, and can be found singularly within her territory.
Red-Eyes Doomstar Dragon - Meteor Dragon, Red-Eyes Black Flare Dragon, Red-Eyes Wyvern, and Red-Eyes Tracer Dragon are all servants of Red-Eyes Black Dragon, all of them given and imbued with fragments of Red-Eyes’ power. This power is the reason they all resemble Red-Eyes, with a direct correlation between the amount they received and their level of resemblance -- Doomstar Dragon - Meteor Dragon received the largest amount, with Wyvern receiving the second largest. Red-Eyes Tracer was given the smallest fragment; still enough to alter their appearance, but far from the levels of Doomstar Dragon. Red-Eyes does not play extreme clear favourites among those given pieces of her power, but Red-Eyes Doomstar Dragon is the most preferred of her close retainers, with Red-Eyes Wyvern a close second.
Black Metal Dragon, like those listed above, was given a touch of Red-Eyes’ power, but unlike those close retainers, it was purely for an aesthetic purpose. It was given only enough to personalise its appearance to Red-Eyes’ liking, and is thought of by Red-Eyes in the same manner one thinks on a pet.
Red-Eyes Lightning Lord - Evil Daemon and Red-Eyes Metal Knight Gearfried, conversely, were neither given power by Red-Eyes herself nor created specifically to serve her. They not a part of Red-Eyes’ inner circle of retainers, nor a spirit thought on immediately when Red-Eyes considers the Red-Eyes archetype -- Lightning Lord more so than Gearfried --, but both are loyal and willing servants all the same.
Fiend Dragon - Black Daemon’s Dragon is often thought to be a fusion of Red-Eyes and another Duel Monster, to the extent humanity created its card with those summoning conditions, but this is not the case. Created from the commingling of Red-Eyes Black Flare Dragons and Red-Eyes Lightning Lords, it is intended to be a bastion of physical offence and powerful force within Red-Eyes’ territory. It does not reside within Red-Eyes’ cavern home as those given fragments of her power do, but patrols her territory combing for threats and serving as a deterrent to those hoping to falsely cross Red-Eyes lands.
Knight of Black Dragon was not a previously existing duel spirit changed to Red-Eyes’ liking, but a monster created solely through Red-Eyes seeking to use her power to create monsters exclusive to her. If an individual points out Knight of White Dragon exists as a likewise counterpart for the Blue-Eyes archetype, she will be quick to refute the legitimacy of the claim, citing that Knight of Black Dragon was created first and Knight of White Dragon is only a poor imitation of her power and strength.
Lord of the Red was a duel spirit prior to becoming a part of the Red-Eyes archetype. It was created on the backs of willing spirits who volunteered to join Red-Eyes as one of her servants, transmuted through exposure to Red-Eyes’ power. They are superior to Knight of Black Dragon, often seen commanding legions of them and leading them into battle. Two Lords of the Red stand either side of the entrance to Red-Eyes’ cavern, guarding the entrance to their mistress’ home.
Summoned Daemon and Meteor Dragon are not regarded as truly being part of Red-Eyes’ retinue, nor are they regarded as beings of any worth. They exist on the edges of Red-Eyes’ territory where it metes out into other spirits’, not permitted to enter but allowed to exist on the fringes of Red-Eyes society through duelists’ insistence on including them in decks with Red-Eyes. They are regarded as cannon fodder, a garden variety spirit available across the Spirit World as a whole, and Red-Eyes herself is barely aware of their existence.
Not all cards associated with the Red-Eyes archetype are spirits born to be Red-Eyes’ servants or forms gifted to her. Some are objects, present in the spirit world and translated over into the card game, while others are separate entirely from the Red-Eyes archetype, linked to Red-Eyes in other ways.
Red-Eyes Black Dragon Sword is not a duel monster as one would believe, despite humanity creating it to be a fusion monster card. It is a physical manifestation of Red-Eyes’ power given to her by Hermos as a marker and symbol of the legendary black dragon. Should she appear in human form, the sword hangs by Red-Eyes’ side at all times, appearing to be black of hilt and red of blade rather than the Red-Eyes inspired design humanity forced upon it. It can take the card-based appearance should Red-Eyes wish it so, but she has found she vastly prefers her own simpler design. Although the Dragon Sword is not a spirit and cannot communicate with humans as Duel Spirits do, one sensitive to the spirit world may be able to sense a hint of something akin to a spirit within it, identical to Red-Eyes’ own spiritual signature and marking it as a part of her.
Red-Eyes Fang With Chain is a weapon forged on Red-Eyes’ own orders. It had no divine meaning or strength as the Dragon Sword does; she had it made for the aesthetic alone. Red-Eyes can summon this to her at will, but rarely relies on it where the Dragon Sword will do.
Keeper of the Mausoleum is a spirit tied by fate and effect to Red-Eyes, but it does not serve her. It was one of the first Duel Spirits to be born, created by the Egyptian Gods for the purpose of maintaining balance between the legendary dragons of black and white. The Keeper resides within a shrine in the Spirit World, one dedicated both to Blue-Eyes White Dragon and Red-Eyes Black Dragon. The shrine is filled with carvings and friezes of the dragons, with the two most prominent features being life-size stone statues of Red and Blue-Eyes. There, spirits may thank the dragons and pray to them for support and aid with the Keeper watching over them. The shrine itself is on neutral territory, far enough away from both dragons’ homes that they cannot fight over who it ought to rightfully belong to; though it does not speak of it, the Keeper disagrees with the dragons’ constant fighting and wishes it did not have to play the role of peacekeeper as well.
Metalization - Magic Reflection Armour is an armour available to both Red-Eyes Black Dragon and Devilzoa. Although Red-Eyes does not wear it constantly, finding the design of the armour unsuiting to one of her calibre, her human form bears subtle homage to it in the form of red armoured vambraces.