Eldar (Part -1)
Once, over ten thousand years past, the Eldar were perhaps the most powerful race in existence, dominating a significant portion of the galaxy and secure in their prosperity. Although there were other intelligent races who possessed advanced technology and potent military power in the galaxy, none was in a position to seriously threaten the state of the Eldar empire. When it came, the disaster for the Eldar people was self-inflicted. With no need to perform substantial work or labor, the Eldar began to pursue their curiosities and desires with all the dedication that only their species could muster. In the later days of Eldar civilization, cults devoted to exotic knowledge, physical pleasures, and evermore outrageous forms of entertainment sprang up. It did not take long for many of the Eldar to pursue a darker path to achieve instant fulfillment as they came to revel in unbridled hedonism and violence.
Eventually, this growing mass of negative psychic energy came into a life of its own and came to consciousness over ten thousand years ago at the end of the Age of Strife as the newborn Chaos God Slaanesh, the Devourer of Souls and the doom of the Eldar. The psychic scream of Slaanesh's birth tore the souls from all the Eldar within a thousand light years of it, sparing only those sheltered in the wraithbone hulls of the Craftworlds. The Prince of Pleasure's awakening was so forceful that it tore a hole between the physical realm and the Immaterium, plunging the Eldar homeworlds into a nightmare existence, trapped within the realm of Chaos. This region is now known as the Eye of Terror, and is the home of the forces of Chaos in the 41st Millennium.
Since this time, which is known as the Fall of the Eldar to the end of Gullieman heresy, the Eldar has been a broken and scattered people, lacking both political cohesion and true purpose. Many of the outlying Eldar colony worlds, whose people are known as the Exodites, have slipped to a more primitive technological level similar to that of some feudal human worlds, while the survivors of the Eldar homeworlds drift through the stars in colossal nomad fleets and their Craftworlds, each independent of the others. All the Eldar have been greatly changed by The Fall and the rise of Slaanesh. However, the alliance with the Imperium has afforded the Eldar the time to recuperate and with that has come the vital boost to their population. What was once simply a battle for survival, has become a fight to retake the stars. Young Eldar often believes that they can rebuild their lost but once glorious empire with fire and passion and the Imperium makes use of them.
Uncertain Future: The greatest dispute between Craftworld happened in the few years just before beginning of the Great heresy which took place in the 31st Millennium. Eldar feared that a great calamity will fall upon galaxy, Ulthwé Craftworld's Seer Council led by the Eldrad Ulthran, tried to understand what lie ahead, Eldrad Ulthran and all other farseers tried to to see the possibilities of the future so that they can manipulate events for eldars survival, they gather around at the Dome of Crystal Seers that contains the Spirit Stones of deceased Eldars which are added to the gestalt spiritual reality of the Infinity Circuit, Farseers togather tried to meditate within the Dome of the Crystal Seers and attempt to divine the future for a interpretation of fate and future of eldars, with dome amplifying their power they encountered infinite number of possibilities, they eventually distilled all possible eventualities into two outcomes.
Outcome One: Victory for Horus
The seers believed that, after the Heresy, a scintilla of the honorable being that Horus once was would remain within the Warmaster, eating at him over what he had done and fuelling a self-destructive sense of self-hatred and loathing that would see Horus fall on his own subjects in an acceleration of the violence of the Heresy, creating civil strife amongst the Forces of Chaos that would culminate in the final extinction of Mankind. The end result of Horus' conquest of the Imperium would be the total extermination of the human species within two or three generations. However, if humanity were to disappear from the galaxy, the Ruinous Powers of Chaos, whose own existence within the Empyrean depended upon the baser collective psychic emanations of humanity, would be extinguished with it.
Outcome Two: Victory for the Emperor
If the Imperium defeated Horus and his Traitor Legions, the seers foresaw the Emperor gives his life to kill Horus, but then becoming a howling, undead rictus trapped within the cybernetic life-support coffin of the Golden Throne, his soul fighting an endless but ultimately losing battle against the influence of the Chaos Gods as his power steadily waned across the millennia. The seers believed that this path would lead to technological and cultural stagnation for the Imperium of Man, and this stagnation would ultimately conclude in irreversible decay. This decay would accelerate and enhance the human misery that contributed to the power of Chaos, allowing the Dark Gods to grow in power and spread their influence across the galaxy, until after ten or twenty thousand years of increasing misery, the entire galaxy and all of its sentient species would be consumed by the unrelenting hunger of Chaos.
Both of the outcomes did not much benefit Eldars, in first outcome there is a possibility chaos will be destroyed with humans, but who can give guaranty in the following years of anarchy eldar also will not be destroyed? This was a too greater risk to gamble on. In second outcome things remain same as they are, chaos will grow stronger and finally dark gods have their victory.
Eldrad Ulthran argued for a third outcome, he tried to convince the Seer Council that while they know, heresy will happen, but if Eldar can control how it will happen then they will be able became much more powerful in postheresy galaxy. He voted to contact one of the primarch and warn humans, he personally contacted Magnus and told him about heresy.
When Horus was saved Eldrad Ulthran was relieved that now first two outcome were obsolete, when the Gullieman heresy happened he understood his folly about how he underestimated power of chaos, he ran to Dome of the Crystal Seers for one last interpretation of fate, he used all his powers to search for a future where chaos atleast be stalemated, then he saw the near future, he in his mind eye saw clash of emperor with Gullieman, than a idea came to his mind, dark gods empowered gullieman by converting him as an anchor, he is their conduit of power, so that he can fight emperor in equal terms, through him, they reach real space, but same way they are now vulnerable to attack if anyone with sufficient powers attack them through their puppet. Only a person has that much power is emperor, Eldrad tried to maximize this one chance. He thought about how Eldar souls immediately consumed by the hunger of Slaanesh upon the death of their physical bodies, soul stones are too crude to stop Slaanesh, they can be destroyed and then their souls will be devoured, even Crone Worlds which are vitally important to the survival of the Eldar because they are the only source of spirit stones, are running dry. The journeys to the Crone Worlds constitute entering the most dangerous areas of the galaxy, and many who go to the Crone Worlds never return, to Eldrad eldars needed a better plan to survive in a cruel galaxy.
It was not possible even by the emperor to permanently kill dark gods that way, but surely he can mutilate at least one of them? To him it was theoretically possible if the emperor consumes Slaanesh's stomach them eldar can be finally free of her. The problem was to make an emperor and other craftworlds support his plan.
Dispute between Craftworld: So he informed the Seer Council of his plan and used his silver-tongue to make them support his plan, even if Ulthwé sides with Imperium and joins them after heresy, it will not be enough, they needed the support of other 4 Major Craftworlds such as Alaitoc, Biel-tan, Iyanden, Saim-Hann. So they were called in a grand conclave to decide which path one should take. After much debate Ulthwé and Alaitoc supported the plan while Biel-tan protested venomously about the plan, they passionately argued with Eldar's legendary arrogance that instead they should use this chance and try to reforge the Eldar Empire, by eliminating the younger races who have "usurped" the galaxy. If mankind falls, then it will be much easier to topple them. While Iyanden supported goal of rebuilding a new realm that would one day rule the Galaxy as the Eldar Empire had once done, they were open for alliance with Imperium and Saim-Hann were neutral about the matter, to placate Biel-tan Eldrad told them of his hypothesis about how they could be free from Slaanesh forever, even Biel-tan could not argue against this, so they proposed, if only if they are free form Slaanesh, they will join Imperium and give their skills and expertise for use of Imperium, even then they will not join without equal status, they are not any other lesser race, they are eldars.
Contacting Emperor: Eldrad Ulthran know the Emperor is a proud man, he will not crave in before their demands that easily, so he waited for a proper moment to contact him, that time came in the middle of heresy. With Gullieman coming with full force, and loyalist who were on terra nearly broken and defeated, Emperor is out of options. In that moment Eldrad contacted him. He informed the emperor of his hypothesis, the emperor was both conflicted and suspicious of Eldar's motive, so he forced Eldrad to swear an oath that if he does this eldar will join Imperium and give humans access of the webway and eldar technology and skills, in return he will give them a equal status as humans in the Imperium, both Craftworld Eldar and Exodites soul will be saved after death of the emperor, while dark eldars soul will remain consumed by Slaanesh for the punishment of their sins. Eldrad strongly demanded that eldars representative be given a permanent seat as a high lord of terra who will be decided by Eldar council, after much debate emperor then agreed that eldars will be given a seat, this seat than belongs to navigators. The Emperor told Eldrad all the hidden secrets and dark truths which navigators tried to hide about them. He knows about those facts because he himself created navigators long ago, they were long slated for extermination after the success of the imperial webway project, with Eldar gives the key to webway they were no longer needed and now disposable, with all the info about them it will a short work for eldar to wipe them out and inherit navigator's power and control over the Imperium. Then the bargain was stuck between man and eldar.