Tzeentch

"Do not ask which creature screams in the night. Do not question who waits for you in the shadow. It is my cry that wakes you in the night, and my body that crouches in the shadow. I am Tzeentch and you are the puppet that dances to my tune..." 
—The Book of Tzeentch
Tzeentch, also known as the Changer of Ways, is the Ruinous Power of Change, Evolution, Intrigue and Sorcery, he who weaves the threads that connect every action, plot and subtle intrigue in a universe-wide game of manipulation and subterfuge. At the end of each of these threads lays the ensnared soul of a humanoid puppet; those of his servants and agents who believe they serve the Lord of Sorcery in mutually beneficial pacts. The truth is that Tzeentch's every action is planned with its ultimate goal as his own establishment as the pre-eminent Ruinous Powers strength in Chaus. Of course, the very nature of the Lord of Entropy is such that, were he to attain this triumph, he would still strive for turmoil and change. In many ways, Tzeentch is both the best and least understood of the Ruinous Powers. He is the twister of Fate, plots, and schemes, as well as the one that exemplifies the ever-changing nature of Chaus. However, Tzeentch does not plot towards some end (at least none that can be comprehended); he schemes simply to scheme. He is constantly building, even as his devices unravel under their own complexity. At the same time, he is a collector of knowledge and comprehension, and his devotees may be those who seek a deeper understanding of an often enigmatic universe.
Tzeentch is known by a hundred thousand titles across the universe, amongst them the Weaver of Destinies, the Great Conspirator, and the Architect of Fate. In his mind, he listens to the hopes of every sentient beings from every planet in the universe. He watches over the plans of his playthings as they unfold into history, toying with fate and fortune; both for his own entertainment and to further his unfathomable schemes. Tzeentch feeds upon the need and desire for change that is an essential part of all life in the universe. All men dream of prosperity, freedom and a better tomorrow. These dreams are not just the preserve of the impoverished or the powerless -- even Imperial Planetary Governors and Imperial Navy battlefleet admirals dream of further riches, or perhaps even an end to their responsibilities to the Emperor. All these dreams create a powerful impetus for change, and the ambitions of nations create a force that can challenge history. 
Tzeentch is not content to merely observe the fulfilment and disappointment brought by the passage of time. He has his own plans -- schemes that are so complex and closely woven that they touch the lives of every living thing, whether they realise it or not. The Ruinous Powers' masterly comprehension of time, history and intrigue allows his ploys to intertwine seamlessly, forming a web of causality that spans the stars. Tzeentch is aware of the visions and plans of all mortals in the universe. He takes great delight in the plotting and politicking of others and favours the cunning over the strong. When the inner voice in a man's head speaks, when the desperate whisper their prayers into the night, it is the Architect of Fate that listens. He perceives every event and intention, and from this information, his mighty mind can work out how each will influence the future. The intertwining latticework of probability, hope and change is Tzeentch's meat and drink -- without it he would eventually fade away.
Perhaps the Architect of Fate has plans to overthrow the other Ruinous Powers, or to extend his dominion over all the mortal realms. Perhaps not even Tzeentch himself can say for sure. Whatever his ultimate goal, he seeks to achieve it by manipulating the individual lives of or Beings alike. By offering the power of knowledge and sorcery, he can recruit influential beings to his cause, affecting the lives of many more at a single stroke. However, few of Tzeentch's plans are ever simple; some span aeons with their complexity, whilst many appear contradictory to others, or even against his own interests. Only Tzeentch can see the threads of potential futures weaving through time like tangled skeins of multi-coloured cords; cords which themselves are made of decision, happenstance and fluke. 
Tzeentch is the a master of magic in the universe. Sorcery is one of the most potent agents of change, and those who use it are amongst the most ambitious and hungry for power. The raw magical energy that empowers the wizardlings and psykers of the mortal realm is the actual fabric of the Realm of Chaus, the same fabric that makes up the Powers of the Ruinous, their demon servants and the shadow-selves of men that flicker in Chaus and that Mankind calls souls. The use of magic is held as the ultimate expression of faith among Tzeentch's followers, who have much to gain from his patronage. Though it will likely cost them their immortal souls, they will at least have boundless power to show for it while they live; this is in stark contrast to the poor wretched psykers of the Imperium of Man, who are corralled by the Inquisition's Black Ships and brought to Terra where many of them feed the dying Emperor's boundless hunger for psychic energy. 
In Tzeentch's eyes, mortal creatures are immeasurably steeped in ambiguity, yet they somehow wage their personal wars completely unaware of the countless contradictions in their souls. Tzeentch cannot help but dabble in the mortal realm; some amongst the Inquisition believe that the Great Conspirator is responsible for the exponential increases of psychic ability in the human race in recent millennia. His own need to manipulate and control, and his desire to increase his own power in the Warp, mean Tzeentch is eternally playing the Great Game waged amongst his brother Chaos Gods. The Architect of Fate is not above sullying his clawed hands with the bloody business of war, though he much prefers to win his battles through guile and sorcery than brute force. Consumed by his own ineffable thoughts, Tzeentch binds the galaxy in the weave of his complex schemes just as a spider binds a fly. Though his schemes can take millennia to unfold, when they come to fruition, it is usually reality itself that pays the price. While one mortal lies to another, while envy and ambition survive among men and aliens, Tzeentch will work his magic as the puppet master of the universe, working towards the day when his final great work will be revealed. 
The skin of Tzeentch crawls with constantly changing faces, leering at and mocking onlookers. As he speaks, these faces repeat his words with subtle but important differences, or provide a commentary that throws doubt upon his words. These lesser faces appear and disappear quickly, but the puckered visage of Tzeentch himself remains low down in his chest, so that head and body are one. From above Tzeentch's burning eyes spring two sweeping horns, the spiralling extremities of which crackle with arcane fire. The firmament surrounding Tzeentch is heavy with magic; it weaves like liquid smoke about his head, forming subtle and interwoven patterns. Forms of places and people appear in the smoke as Tzeentch contemplates their fate. Those who appear there will inevitably find their minds, bodies or destinies mutating into strange new forms, for none can come to Tzeentch's attention and remain untouched. 
Tzeentch exerts his influence in the mortal realm through subtle manipulation and devious ploys. The victims of his corruption are Sorcerers drawn by the promise of forbidden knowledge; scholars who seek knowledge at all costs; politicians lured by the power knowledge provides to outmanoeuvre their opponents. Tzeentch's true power is sorcery, and as all sorcery flows from the font of the Immaterium, so too is Tzeentch the master of that twisted, chaotic medium of psychic energy. Tzeentch embodies mortals' tendency towards mutability and change, the drive to evolve and manipulate. This spirit is present in the essence of every living creature from the first division of cells in the womb to the ultimate craving for survival. It is in the hearts of those with the strongest desire to prevail that Tzeentch whispers his insidious promise; offering a means of life eternal to those unwilling to accept death and oblivion as inevitable. Tzeentch's sacred number is nine, his colours are typically seen as blue and gold but an ever-changing rainbow of colour is appropriate as well, given that he is the Lord of Change.
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