There is an underworld in Mare City, deeper even than the one of organized crime so many know. As with all things, magic has a dark side and there are those that barter and trade in its more terrible aspects. Business is business, even in the world of magic.
The godfathers and patriarchs of this arcane world are not as easily dealt with as their mortal counterparts. Worse, these beings do not die natural deaths and their competitors cannot simply wait and hope to outlive their rivals.
What do you do when you need an Immortal killed?
You call Oliver Black.
He can kill anything.