Though none amongst the Stormhosts realise it, Severin Steelheart and his fellow Liberators – Angharad Brightshield and Obryn the Bold – have as critical a role in the future of the Stormcast Eternals as the Sacrosanct Chambers deployed to secure it. They were once simple Liberators, sent to reinforce the Knight-Questor Kantar Gloryborn on his mission to delve into the bleached ruins of Shadespire and investigate rumours of a strange, magical glass that held power over mortality. Since becoming trapped in the soul-torn reflection that is the Mirrored City, they have learned more of shadeglass than any other in Sigmar’s hosts.
Fighting through the undead denizens of the Desert of Bones, Gloryborn and Steelheart made their way into the desiccated, soulless remnants of the city that had once been Shadespire. There the Liberators became separated from their fellows during a battle with a gang of brutish orruks that were sacking the Necropolis of Trense. That attack was so intense that a section of the necropolis fell away, plunging Steelheart and his fellows into the labyrinth beneath.
Seeking to reunite with the rest of the brotherhood, Steelheart and his fellows came through the cave networks to find their way blocked by an underground river – made not just of water, but of trillions of angular pieces of broken glass. Wading across it, they were assailed by a great surge of water, which carried them over the Waterfall of Shards. When they emerged, half-drowned, they were no longer in Shyish, but the twilight realm that is the Mirrored City.
Since that day, Steelheart and his warriors have been trapped, unable to find their way out and forced to constantly battle the countless warbands of foes who have also found their way into this place. It is an endless cycle, for even should they be overcome, they awake the next day to face their ordeal again, for all in the Mirrored City are cursed by Nagash to endure an eternity of inescapable death. Steelheart and his champions did once find the Waterfall of Shards flowing backwards, but learned it would only bear the weight of one of their number. Instead of separating, they sent a cache of soul-rich shadeglass back to Shyish, hoping it would be found by their old comrades so they could unlock the mysteries within.