Yien-Ya-Long, translated as "Flamefang" in Reikspiel,[1a] and also known as Dar-Sorakshi,[4a] was a massive, serpentine Chaos Dragon sworn to the service of the Chaos God Tzeentch that once laid waste to Grand Cathay. It was slain by Archaon, the future thirteenth Everchosen of Chaos, during his quest to claim the Eye of Sheerian.
Flamefang has been described as serpentine, similar to the Cathayan Dragons who rule Grand Cathay,[1b] although it is also described as having wings and three heads.[2a] The Chaos Dragon's original flesh had long ago decayed and been replaced by pure spirit that it clad in the flesh of its devoured victims. It terrorised Grand Cathay for over a thousand years before it was defeated.[1a]
The ancient creature was summoned again by the Chaos Sorcerer Khezula Sheerian and unleashed upon Archaon's mutinous army in the Far Sea. The Chaos Dragon also turned on Archaon, seeing him as the worthier prey. It destroyed the copy of the Celestine Book of Divination the future Everchosen carried, devoured the Eye of Sheerian carried by the Chaos Sorcerer and sank most of his fleet.[1b] As Archaon arrived in the Southern Wastes, the Dragon hunted him further, until Archaon managed to evade it by pushing it into a lava stream at Mount Ceno, wounding it enough so that it would flee.[1b]
When Archaon had claimed the Armour of Morkar, he faced the Chaos Dragon again. The armour's enchantments protected him against the fire of the Dragon and when Archaon was devoured by it, he fought it from the inside, fighting against the assimilated flesh shades of those the Chaos Dragon had devoured before, as well as half-born Draconic embryos the Dragon carried inside its body.[1c] Archaon managed to kill the monstrosity and banished its soul back to the Realm of Chaos with Sheerian's aid.[1c] Afterwards, he took the Eye of Sheerian for himself, granting him the second of the Six Treasures of Chaos he needed to claim to become the next Everchosen.[2a]
Yien-Ya-Long might have been one of the four missing children of the Dragon Emperor of Grand Cathay.[3a]