Symbols: Bones, the all-seeing eye
Clan Troops: mainly manifests as the undead corpses of soldiers (various Clans) on the battlefield
Any place with a large number of dead automatically spawns undead. These undead corpses are only capable of looting, and are generally not that dangerous.
But sorcerers who use undead magic in the pursuit of immortality commonly enslave the undead to form fearsome troops. And thus, the other Clans started to notice the existence of the undead. But every sorcerer works alone, and it is difficult for others to figure out how to communicate with the Specters. All we know of them are spine-chilling rumors.
Undead magic is a kind of magic left behind by the demons, and is markedly different from the magic that is commonly used in Vollandia (ie. the magic taught by the Dragon).
Does not populate any kind of region in particular.