The four Gods of Chaos
To understand Chaos, which is in itself impossible, one must first understand the warp. The warp is a dimension adjacent to ours, in which emotions and thoughts can become living things, which can manipulate the warp and indeed the minds of mortals. These creatures are sustained by the thoughts of mortals, and seek more and more of these thoughts. For these creatures to gain this, specifically thoughts which taste fine to them, mortals must worship them, and in return those who worship a certain god are gifted with abilities and powers beyond imagination, for instance those gifted by Tzeentch are granted powers over sorcery and arcane knowledge, while those gifted by Nurgle are granted viral based mutations, such as extra limbs or other such things. It should be known, however, that too many blessings can often result in the person becoming a warp spawn, forever mindless and feral.
Khorne is the Chaos god of hate, bloodshed, war, and violent death, as well as honour, bravery and martial skill. The World Eaters Chaos Space Marines are dedicated to him and his cause: The shedding of blood and the defeating of all enemies. Every act of killing gives Khorne power; the more senseless and destructive, the better. Khorne's daemons are Bloodthirsters, Flesh Hounds, and Bloodletters. His opposite is Slaanesh, due to Khorne's dislike of the other god's effeminate hedonism; in addition, Khorne's value of "death to all" is at odds with Slaanesh's "enjoy life as much as possible through sensual extremes". Khorne's rivalry with Slaanesh is also fueled by the Eldar god of war, Khaela Mensha Khaine, being first defeated, dominated, then fragmented by Slaanesh. Khorne is viewed as the mightiest of the four great Chaos powers.
However, it must be noted that Khorne's followers seek not to cause pain - pain is the domain of Slaanesh, as is pleasure. Although Slaanesh is the god of pleasure, including Sadism and Masochism, he is a god of producing feelings, not tangible results. Slaanesh is interested in playing with his victims, not dominating them as Khorne would. Khorne's followers wish only to kill and to win, because while the blood of their victims strengthens Khorne, suffering empowers his nemesis Slaanesh. Khorne is a god of getting things down. Khorne "plays to win", as opposed to Slaanesh who "plays for fun". Khorne would kill a fly with an atom bomb. Slaanesh would kill an elephant with a sewing needle.
Khorne himself is seen as a mighty being, clad in brass armor, sitting atop a mighty throne of skulls standing in a sea of blood - the throne is made up of every skull his followers take (as well as the skulls of his fallen champions) and every droplet of blood they spill.
The battle-cry of the followers of Khorne reflects his desire for wanton violence: "Blood for the Blood God! Skulls for the Throne of Khorne!" Alternatively, they may cry, "Skulls for the Skull Throne!" In the throes of violence, Khorne's followers are also known to bellow, "MAIM! KILL! BURN!" repeatedly while hacking apart their enemies. Also, Khorne's Chosen berserkers often shout "Break their backs!" while in the thick of battle. The followers of Khorne seek nothing more than to spill the blood of their enemies and kill. They have even been known to fight amongst themselves if they have no foes to fight with at the time, as a day not spent killing is a day wasted in the eyes of Khorne.
The Greater Daemons of Khorne are called Bloodthirsters (other names given to them in background are Blooded Ones, Lords of Skulls, High-handed Slayers and War Given Form). Of all the Daemons, they bear the greatest resemblance to stereotypical demons (Baphomets), having a human body, cloven hooves instead of feet, leathery bat-like wings and horned dogs-heads. An earlier model of the Bloodthirster replaced the dog-head with an ugly human face, but recently the model has gone back to its canine-featured roots. They wield a fiery whip and a massive two-headed battle-axe (possessed by another Bloodthirster in earlier editions) simultaneously in battle. They are the most combative of all Daemons.
The Daemons of Khorne are called Bloodletters, ugly, horned humanoids with cloven hooves who tote blood-drinking battle-axes or swords.
The Daemon Beasts of Khorne are Flesh Hounds, monstrous and ferocious, pseudo-canine creatures notorious for their ability to track down their chosen prey.
Champions of Khorne, whilst being bloodthirsty combat specialists, are often seen riding Juggernauts of Khorne into battle. These mounts are part daemon,and part hell-forged brass machines. They are capable of charging through their prey without pause, causing mass carnage equal to that of the champions on top, who are probably taking skulls by the second with their chain-axes.
Khorne's Sacred Number is eight and, where possible, his warriors will form up into squads of this number. Khorne's colors are blood red, black and brass.
Slaanesh is the Chaos God of lust, excess, decadence, pleasure, perfection, hedonism and pain. Slaanesh typically appears in an androgynous form in which it is a woman on the right side and a man on the left with two sets of devilish horns growing from its head. It can however assume any form; male, female, hermaphrodite or asexual, but prefers male bodies. Its sacred number is six. It is known as the Prince of Chaos or Prince of Pleasure.
In the name Slaanesh is a corruption of the Chaos term Slaaneth (Slaa meaning "ecstasy" or "pleasure" and Neth meaning "lord" or "prince"; hence, the Prince of Pleasure).
Slaanesh came into existence during the time the Eldar called The Fall. He was born from the Warp-reflection of the decadence of the Eldar. The Birth cry of Slaanesh created the Eye of Terror and slew most Eldar and their gods, except for Khaine, who was dispersed into many pieces, and the Laughing God. Other survivors included the Harlequin, and those Eldar who were very far away from the Eldar Worlds. Slaanesh is served primarily by the Emperor's Children, hedonistic psychopaths who wield unique sonic weaponry in battle.
Slaaneshi daemons include: Daemonettes, feminine creatures whose seductive bodies are at contrast with their grotesque claws and lightning speed; Steeds, lurid snakelike creatures who lash with their prehensile tongues in combative support of their riders; Fiends, bizarre creatures that are a combination of human, reptile, and insects who can produce a half-sonic/half-psychic song that is lovely to the Prince of Chaos but deadly to his enemies; and the Greater Daemons called Keepers of Secrets, each a huge and indescribable creature whose very presence is capable of bringing the bravest warrior to his knees in simultaneous waves of anguish and ecstasy.
The symbol of Slaanesh combines the conventional symbols for male and female, although it is seldom worn openly by his followers. In its place they often wear items of jewellery bearing erotic motifs. Followers dress in robes which are often opened to leave the right side of the chest uncovered, a requirement of many of the rituals involved in his worship. Pastel and electric shades are the chief colours, although white is often used as well. These colours are also sometimes carried over into everyday wear, although they may be modified to fit in with current fashions. Regardless of any considerations, all Slaanesh followers wear garb of sensuously high quality.
Slaanesh has a neutral attitude to many of the gods of Chaos, and is generally too caught up in his own pleasures to be interested in alliances and co-operation. Particular enemies are the followers of Khorne, whose belief in death is completely opposed to Slaanesh's principle of a life of unrestricted sensual extremes. Followers of Nurgle and Tzeentch are subject to Slaanesh's usual neutral attitude. - Realms of Chaos: Slaves to Darkness
Nurgle is the Chaos god of disease, decay, despair, destruction and rotting death. He is the second oldest of the four Chaos gods and is the most involved with the plights of mortals. Many of those affected by his poxes usually turn to him in order to escape the pain caused by sickness. Nurgle is depicted as a large hulking figure covered in oozing sores and vivid marks of decay. The traitorous Death Guard Chaos Space Marine Legion serve him solely.
Nurgle's anti-thesis is Tzeentch, the Lord of Change, because, where Tzeentch seeks to build, and plot, and scheme, Nurgle only seeks to destroy, and break down.
Nurgle's sacred number is seven, His colours those of rot and ruin.
Nurgle also embodies the will of mankind to struggle on no matter what opposes them, albeit perversely. Suffering, death, etc: the human race pushes these things from their minds and tries to forget them by living in the moment. For this reason he, his daemons and followers usually demonstrate a disturbing joy at the pestilence that he inflicts, seeing the plagues as gifts and the cries of their victims as gratitude rather than agony. He is often referred to as "Grandfather Nurgle," "Father Nurgle" or "Papa Nurgle" by his followers because of this paternal stance.
It has recently been uncovered that Nurgle is in possession of the Eldar God Isha. (rescued from Slaanesh's imprisonment) He utilizes her for his experiments creating new contagions and diseases to spread into the universe. With her powers of healing, she quickly regenerates from these tests, although Nurgle gleans what information is desired from the temporary effect. Secretly, she whispers the cures to these diseases to the mortal of the universe.
Tzeentch is the god of change, mutation, and hope, and the master of sorcery. His realm is woven from the raw fabric of magic, threaded upon deceit and conspiracy. Of all the outlandish landscapes of the realm of chaos, Tzeentch's Domain is the most bizarre and incomprehensible. Tzeentch himself takes many forms, and his plots and deceits are unimaginably complex, so large that no mortal can discern his final goal. Mortal followers of Tzeentch are often gifted with grotesque mutations that grant them superior strength, agility, or even heightened mental faculties. Of all Chaos Sorcerers, followers of Tzeentch are the most adept at bending the fabric of reality to their whim, wielding the many-colored 'Fires' of Tzeentch to terrifying effect.
The Sacred Number of Tzeentch is Nine, and his colours are either blue and gold (as seen with the traitor Thousand Sons legion who serves him exclusively) or an everchanging rainbow of colour.
Tzeentch's minions come on a broad Spectrum of shapes, sizes, and colors. Screamers are ethereal, Manta-ray like daemons who float gracefully through the air, while Horrors are gibbering tangles of mouths, arms, and horns. Flamers are living conduits for the fires of Tzeentch, long, hollow tubes of flesh with mouths at every end. The greatest and most terrifying creature of Tzeentch, however, is the Lord of Change, a majestically bizarre Daemon that looks part man, part vulture, covered in iridescent scales and wearing flowing robes.
Tzeentch's greatest enemy is Nurgle, whose representation of stagnation is in contrast to Tzeentch's constant change.
Anutha one bites the dust, AH!