Idol of Balthazar
It is an idol of Balthazar, the human god of blood and butt-kicking. Therefore, it is imbued with...well, all that sort of thing.
The idol of Balthazar is a powerful magical idol, which is linked to the power of the Human God, Balthazar. It places a murderous power upon the user, turning them into an Avatar of Balthazar. The more they kill, the more powerful they become. But the power inflicts a cost on the soul—if the user is not strong enough, it will consume them as well, turning them into a ravaging, blood-crazed psychopath.
In 1325 AE, it was recovered by the Mane Warband outside the Black Citadel, and given to the Durmand Priory courtesy of Rytlock Brimstone. After Claw Island fell to Blightghast the Plaguebringer, it was used to defeat Thadeus Ghostrite. According to Gixx, the idol was no longer enchanted afterward—the human god of mass murder is not a deity that likes to use the same tactic twice.