Melekh the Changer was a Chaos Lord of Tzeentch created as part of the fluff surrounding the release of Warriors of Chaos during the early "Hordes of Chaos" approach and as part of the build up to the Storm of Chaos campaign. He was listed as one of the Lieutenants of Archaon during the retconned Storm of Chaos event.
Once a humble blacksmith of the Aesling tribe, Melekh was set on the path to damnation when the village shaman lost control of a spell intended to help Melekh's wife Kayla give birth safely, killing the woman and ensuring that Melekh's son was born a deformed mutant with a bird-like head. The boy was deemed a good omen by the village chieftain, who named him Cyspeth and proclaimed him a sign of favor from their daemonic patron Zarechgor.
While the villagers were celebrating Cyspeth's birth the chieftain suddenly announced that Zarchgor had spoken to him, decreeing the village was to hold a tourney; the mightiest warrior in the village was to become the new apprentice to the village shaman, Gaerkkol. This privately filled Gaerkkol with horror, for he had knowledge of the Prophecy of Fate, which foretold the coming of Archaon and his seeking of lieutenants amongst the tribes he was to gather to his banner. Fate and skill ensured Melekh won the tourney and Gaerkkol, in an attempt to protect himself, sent Melekh on what he believed would be an impossible task: to find the True Name of Zarechgor.
Unable or unwilling to back down, Melekh left for the Chaos Wastes, leaving the infant Cyspeth in the care of the shaman. Unkown to Melekh the treacherous shaman had only agreed to the task to secretly try to turn the boy into an ace in the hole in case the boy's father somehow returned. Under his care Cyspeth quickly grew in power, even coming to surpass his teacher in time. Melekh meanwhile found a portal into the Realm of Chaos itself after some time. There, he was beset by daemons of Tzeentch, but by mastering his fear, he forced them to submit to his will, enslaving an army of gibbering Horrors, flickering Flamers, and rapacious Screamers to protect him as he sought out Zarechgor, a Lord of Change. Riding atop a burning Disk of Tzeentch forged by his own will from a fusion of metal, Screamer flesh, and magic Melekh quested on, destroying daemons of all four gods as he sought out Zarechgor.
When the Lord of Change finally stepped forth, he scattered Melekh's army with a gesture. When Melekh demanded Zarechgor share his True Name, the greater daemon struck him down with blasts of spell flame. Even as he lay dying, though, Melekh continued his questioning - and, for a moment, Zarechgor allowed the question to fill his mind, his thoughts becoming corporeal around him. Melekh's horrors chanted the name in a chorus, and with his last breath, Melekh spoke the daemon's Name.
This bound Zarechgor to Melekh's soul, healing his wounds and bestowing him with the daemon's arcane knowledge and power. Gifting his new master with an enchanted blade, Zarechgor opened a portal and sent Melekh and his daemonic minions back to the real world. There, he found twenty years had passed, and his army of daemons was forced to do battle against his former tribe under the watching eyes of Archaon. Unfortunately for Gaerkkol, his plan to use Cyspeth against his dad backfired horribly for, at the height of the battle Cyspeth decided to support his bio-dad instead of his surrogate one and killed Gaerkkol. Melekh thereafter became Archaon's lieutenant, with both the surviving Aeslings lead by Cyspeth and the daemons alike swearing their allegiance to the Everchosen as well thus fulfilling the prophecy.
During Archaon's subsequent assault on the Empire, the hosts of Melekh easily took control of the Brass Tower in the Central Mountains before moving on to besiege the castle of Bohsenfels. Unfortunately for Melekh, what should have been a simple nuisance along the way ended up delaying his forces for a considerable amount of time. Despite employing all manner of tricks and sorcery, the defenders of Bohsenfels were able to repulse all of Melekh's assaults causing Melekh and his son to argue over strategy and tactics.
Enraged by this delay Archaon finally lost his patience and went in person to Bohsenfels to deal with the problem himself. Archaon, accompanied by the feared riders of the Swords of Chaos, arrived in Melekh’s camp during the sunset hours on the thirteenth day of the siege. His presence brought about a halt in the combat during which he called on Melekh's soldiers to withdraw from the walls and listen to his words. This pause brought cheers from the ignorant defenders of the castle, especially from the mercenaries who had initially been paid to defend the castle and who now fought only to survive, though the celebrations would prove to be premature and short-lived. Archaon meanwhile was busy castigating Melekh and his forces, uttering the curses of the Gods on the followers of Tzeentch for not being able to take the castle, and to serve as an example for others, the Swords of Chaos killed five hundred of the warriors. Then shortly after the dripping heads of Tzeentch's dead followers were piled up on a large pyre, Archaon turned and personally beheaded Melekh. As an ominous silence descended on the spot Archaon proceeded to order the mutated Cyspeth to take over command of the surviving troops. There was no need to warn him of the fate that awaited the new champion of Archaon if he failed as his father did.
This proved to be a smart move as under Cyspeth's guidance the army finally succeed in their objective and brought Bohsenfels low. With that settled Cyspeth was subsequently ordered to leave only a small entrenched force at the conquered castle and then lead the rest of his Tzeentchian forces on an advance through the town of Ferlangen and then onwards beyond the passes traversing the mountain of Nordberg in the Middle Mountains.
Afterward, Cyspeth was last seen during the final battle of Sokh in the province of Middenland. After Archaon had failed to break through the walls of Middenheim, Cyspeth and his Tzeentch supporters together with Be'lakor unleashed a veritable magical firestorm against the flagellant army of Valten, causing countless casualties among the Sigmarites...not that any of this actually mattered ultimately, what with GW hitting the big old UNDO button on the events of the Storm of Chaos and then subsequently replacing the event with destruction of the world during the ACTUAL End times. Something which featured neither Melekh or Cyspeth.
Age of Sigmar
While neither Melekh or Cyspeth may not actually appear in AoS, it is notable that Melekh’s model was used to represent the Fatemaster, a Arcanite Chaos Lord on a Disc.