Aether-Walker

Ecology
Aether-Walkers are the victims of psychic plagues like the "Whispering Sickness." They are not traditionally undead, but rather mindless, ambulatory corpses whose nervous systems have been hijacked and reanimated by the very Aether-networks they once utilized. They are often found in the lower wards of Kigum, moving in silent, rhythmic groups.
Combat Mechanics
Aether-Walkers move with a jerky, unnatural speed (40 feet) and have "Echolocation," allowing them to perceive creatures through walls. On a hit, they attempt to grapple the target, whispering "Necrotic Static" directly into their mind (dealing 1d6 psychic damage). They are immune to the charmed and frightened conditions and will relentlessly pursue the source of any noise above a whisper.
Loot
The bodies of Aether-Walkers often hold "Crystalline Residue" in their joints and eyes. This residue can be harvested and used as a minor component for crafting or as a fuel source for low-level Aether-tech.