The Second Wall
The Second Wall we built with our blood and bones, and still we build, to keep the hand of the Enemy from our throats.
Death has always been the great equalizer; it comes to all, weak and mighty, high and low. But has been a long time since death has been the end.
When one of the Hin dies, they are brought in state to a temple of Urogalan. There, their life is celebrated one last time before they are given their ceremonial death mask: a face blank and featureless save for unblinking eyes. This symbolizes the passing on of the soul, and the beginning of the proud and endless service of the body.
The mask is the first step of a ritual of mummification that takes several days. The body is placed in an assembly line that extracts its blood and fills its veins with alchemically treated fluid; armor is grafted to its skin, weapons to its arms. At the end of the process the corpse is placed into a chamber inscribed with the jagged and curling script that binds blood magic. It will emerge as a soldier that does not feel pain, does not question orders, and cannot be possessed by the enemy. It marches, one of many, beyond the city Walls, until it reaches the ring of other undead who surround every city. This is the Second Wall; the sleepless army that keeps the White Legion at bay.
The forces of the Second Wall are directed by music: bells and pipes keep them sedate, swaying gently in time with the peals as they shamble from place to place. Horns and drums call them to action, directing them in labor and battle. In the absence of music they become unpredictable, wandering away from their posts, attacking each other and Hin alike. Most rampant mummies can be brought back to heel when the music returns.
The Second Wall do not feel pain or fatigue, and repairing them is much simpler than the initial animation: while hundreds are lost in combat with the Legion every year, their numbers nonetheless grow steadily. Today, they are a horde, vast and formidable: some days their shuffling, and the pealing of the mighty bells that keeps them calm, is louder even than the wind outside.
The dead do not direct themselves. Someone must remain with them outside the walls, calming them, repairing them, directing them. Many of the Hin have always had a nomadic tradition, and those nomads who embarked on the Exodus chose to take on this grim and thankless role rather than wall themselves in with the rest. These were the first Shepherds. Nomads they still are, though in ways unrecognizable to their ancestors.
The Shepherds have survived in the harsh winter beyond the Walls with a totemic tradition that came into being almost alongside the Church. Many strange beasts died when the world froze, their corpses mummified by the frost of the wastes. The Shepherds search for these, dark shapes buried under ice flats and weathered bones poking from snow drifts; when they find one, they excavate it and reanimate it to serve as a guardian and companion to the tribe. The tribes congregate around the largest specimens, which they turn into moving fortresses to seal against the cold. such as the great Dortoka-Brekh, a tortoise with a village built atop and into its shell, or Iwakpaus, the great ship built into the skeleton of a whale.