Return to Mistborn. 
Join the hunt for a mysterious assassin.
The criminal elite of Elendel were invited to an auction - which became a massacre, when an unknown assailant slaughtered everyone in attendance.
Now Wax and Wayne, both able to use magic, both lawmen from the rough and ungoverned frontier territories, are on the case.
All the clues suggest the killer is a rogue kandra called
Bleeder - a secretive, almost mythical, figure who strikes from the shadows - and that the governor is the next target.
Bleeder, and the conspiracy behind the killings, has to be stopped. Before the city is plunged into chaos.