Where other Stormcast Eternals are a hammer, the Knights-Zephyros are a scalpel, pursuing the champions of Chaos with single-minded ferocity. While these warriors are assassins first and foremost, their way is not to blend with the shadows but to instead carve a bloody path to their unfortunate targets by brute force.
Often, the Knights-Zephros battle alongside the Vanguard Auxiliary Chambers, well suited to their fast paced methods of making war and capable of riding the winds-aetheric alongside the Vanguard-Palladors.
During the Age of Myth, Sigmar battled many feral monsters and rapacious demigods, striking them down to protect his tribes. One such beast was Ulfdengnarl, the Great Wolf of the Howling Winds, and as the white-pelted beast died, Sigmar trapped its endless, baying cry in a crystal shard. It was this divine relic that the God-King employed during the creation of his first Knights-Zephyros.
Mortal killers and assassins of Chaos champions, these lone warriors were imbued with Ulfdengnarl's chilling cry as they passed through the flickering crucible of reforging. Those that survived were blessed with the Great Wolf's inhuman instincts, his gale-force swiftness and his single-minded gift for hunting prey.
Sigmar sent the first of his Knights-Zephyros to join the Vanguard Auxiliary Chambers, there to fight alongside the Rangers in the wildest and furthest flung war zones of the realms. The Knight-Zephyros' role is simple, and symbiotic with that of the warriors they fight alongside.
Each is assigned a singular target, a nemesis that is invariably the most powerful and influential enemy leader operating in that region. They use the Rangers' attack as cover to close with their target, following in the slipstream of their wind-shifting mounts and employing blistering speed to catch the victim unawares.
Fighting with whirling blades, leaping and dodging as fast as thought, the Knight-Zephyros rains blows down upon their victim. Their attack is relentless, savage, a hailstorm of perfectly-placed strikes that soon finds a chink in even the most skilled enemy's guard. Hacked and hewn, the victim falls, leaving their warriors leaderless and engulfed in a panic that the Rangers are quick to exploit with lethal efficiency.