Uredinum is the prized leaf-edged sword of Praepositus. Other than the un-cloned humans, it is the last pure artifact from the Earth of Praepositus and Aeturnus. Other than its ownership by Praepositus, the sword experienced a relatively quiet existence until it was enchanted by TBS, who gave it an internal burning effect.
It is this enchantment that gave it its name. In the tongue of Praepositus' forefathers, it translates as 'burning sting'. From this point onwards, Praepositus favoured the burning sting over his previously commonly used spears. This continued until Praepositus was ambushed by Blackout's knights aboard the Ironclad. He escaped with his life, but without his prized sword.
Desperately wanting back his sword, Praepositus tried to summon it. It worked at first, but then Praepositus abandoned the attempt, coming to the conclusion that his powers were superstitious.
Roughly halfway between Praepositus and the Ironclad, Uredinum lay floating in the abyss before planting itself into an ice planet. It was recovered by someone named Usagi Yojimbo, who decided to keep the sword.