Concept and creation
The concept of Haydon, mysterious creator-god of Haydon IV and the Haydonites, originated with Robotech creator Carl Macek as part of the backstory he developed for the Sentinels series. Per Macek's notes, published in Robotech Art 3, his original vision for the Haydonites had them constantly beaming information out into space, to what they believed to be their long-lost creator, Haydon. Whether or not Macek planned for Haydon to have any more involvement in the story, or to simply exist as part of the Haydonites' history, is unknown, but the idea of the absent god was seized upon by author Jack McKinney and incorporated heavily into his series of Robotech novels, beginning with The Sentinels and culminating in The End of the Circle.
The 21st century reboot of the Robotech timeline that relegated all previous non-cartoon material to a position of "secondary" continuity has left Haydon's position in continuity very vague; it is unknown if his role in the Sentinels storyline still exists, and certainly, the events of The End of the Circle have been entirely overwritten. The only mention of the character in the rebooted timeline thus far has been an exultation from Exedore using his name at the end of the trade paperback edition of Prelude to the Shadow Chronicles. With this in mind, this article covers Haydon's history as detailed by the novels, as this is the only real source of information on him.
Quest for transcendence
The incredibly powerful being known as Haydon was both a singular being and an entire race all in one - a cosmic giant able to divide the mass his body into potentially innumerable smaller identical duplicates. One of the first great intellects in all existence, Haydon's goal was to master the secrets of creation itself. His studies of the universe led him to immortality, and far, far beyond - in time, he eventually came to know everything the material universe had to offer, but still knew there was more, beyond his grasp. Seeking to attain transcendence and move beyond the material world to further his explorations, Haydon failed time and time again, eventually coming to the regretful conclusion that he had evolved as far as he was capable. That did not mean, however, that another race would not be able to accomplish this feat.
And so, Haydon set about manipulating other planets and species in the region of space that would become known as the Local Group, in the hope of evolving them to a point where they could do what he could not. First, Haydon forged a symbiotic connection between the vulpine Garudans and their planet's biosphere; second, he kick-started the evolution of the crystalline lifeforms of Spheris; he gifted Peryton with a telepathic engine that inadvertently drove the planet into an unending war; and he created an artificial world controlled by an artifical intelligence which, owing to its nature as his fourth work, was dubbed "Haydon IV". Later still, he blessed the planet of Praxis with artificial insemination technology that allowed its all-female population to propogate.
Two worlds in particular caught Haydon's attention: a small, blue planet and an incredible flower rich in bio-energy that was native to it, and the planet Optera, home to a race of near-mindless slug-like creatures known as the Invid. The Invid were at an evolutionary dead-end, so Haydon transplanted the flowers from their homeworld to Optera, where the Invid immediately developed an incredible symbiotic relationship with them. A mutated strain of the flowers that became known as Sekiton was sent to the planet Karbarra
His tasks done to the fullest of his ability, Haydon elected to enter hibernation, converting his physical body into data and merging with Haydon IV, to be reawakened by the planet's Awareness when one of the races who had felt his touch finally attained the long-sough goal of transcendence. His legend lived on throughout the local group, with statues and monuments to him existing on nearly every world he had visited.
While on his quest to seed the galaxy with the Flower of Life, the Tiresian scientist Zor communed with Haydon IV's Awareness, and learned of Haydon's history and mission. The Invid Regess similarly learned more of Haydon through contact with the Awareness; specifically, she came upon the sleeping data-form of the nascent god, and briefly roused him from his slumber, only to have him cast her out of the planet's mainframe because she had yet to achieve his goal. To spur her on her way, he left her with a single clue: "seek the Protoculture".
Haydon's experiments bore fruit in the year 2044 when the Regess's experiments in evolution culminated in the transubstantiation of the entire Invid race, who shed their physical forms, became merged with Protoculture as a singular entity, and travelled through the black hole of Ranaath's Star to the void beyond reality. Responding to this event, Haydon IV's Awareness began preparations for Haydon's return, removing the planet from its orbit and moving it into the vicinity of Ranaath, and beginning the production of spherical ships that could safely make the journey through the black hole, piggybacking on the Invid's trail.
The Robotech Elders arrived on the planet to bear witness to the recreation of Haydon's physical form, then propositioned the near-god with a deal: knowing he would require Protoculture to power his ships, which now no longer existed, having merged with the Regess, they would lead him to a source of new Protoculture in exchange for being allowed to rule the universe after he let. Haydon agreed, and the Elders directed him to Optera, recently re-seeded with a new Flower of Life crop and occupied by the Praxians. Adopting a female aspect, Haydon addressed the Praxians directly, and ordered them to gather the flowers for him, after which, the Elders sent him to Tirol, to claim the new Protoculture Matrix created by Emil Lang, Cabell and Rem, to convert the flowers into Protoculture.
His tasks done and his ships fuelled, Haydon immediately betrayed the Robotech Elders and dragged them along with him as he travelled through Ranaath's Star and into the extra-dimensional "newspace" created by the Regess. Haydon and the Regess collided, and Haydon triumphed, taking possession of newspace to use as a tabula rasa for him to conduct his experiments upon, leaving the old world behind.
Behind the scenes
Haydon was a featured mystery and mythological figure in the Sentinels comics and novels. Controversial amoung some fans, the figure essentially replaced Zor as the creator of Robotechnology and the being that spread Protoculture. A timeline published alongside the Sentinels comic series suggested that there was a connection between Zor and Haydon, leaving open the possibility that they were one in the same. It's unknown what role Haydon plays in the rebooted continuity, or if he even exists.