Well, looking over the comments, this guy is still very much in the "larval" stage compared to the NPC Kommisar has been outlining. He's still young--about Dresden's age--and is taking his advancement slow and steady, often testing out and refining improvements on hapless victims before applying them to himself.
The PCs have actually tussled with him before, where he was one of the secondary warlocks in a cabal that the PCs had to deal with; they ended up not being as thorough as they should have been, being somewhat distracted by the horde of demons that the leader had summoned before they arrived, leaving him only mostly dead.
His primary contribution to that battle, actually, was to have engaged in some fast and crude--meatball level--augmentation of some of the cabal's minions, using the biomass of some dead minions as material or grafts, and gave them bone spurs (Claws) and dermal armor (Inhuman Toughness). So, when the PCs came back to kill or be killed, they found that the minions were a little tougher this time around.
At present, he's in the employ of a local mob boss, who is more than happy to leave him to his research so long as he helps produce some designer drugs and occasionally improve some of his men with some of the Inhuman tier abilities.
Here are his current stats as of comments from this thread; he's not the Big Bad, or even the Dragon, so he's not that incredibly nasty; he's more the bad penny that the PCs can't get rid of.
High Concept:
Biomantic Flesh Artist
Trouble:
The Things I Could Do With You
Other Aspects
Freakish Form
The Mind Is A Plaything Of The Body
I Have A Heart—It’s Just Not Where You Expect It To Be
Lamarck Was Right
Unashamed
Skills:
Great (+4): Scholarship, Conviction, Discipline, Endurance
Good (+3): Craftsmanship, Lore, Alertness, Intimidation
Fair (+2): Athletics, Investigation, Presence, Rapport
Average (+1): Empathy, Deceit, Contacts, Fists
Stunts:
Flesh Artiste: You know the human body; how to mark it, how to change it, how to alter it and how to best be about it. Gain a +1 to Craftsman rolls when engaging in bodily alteration and you are done 1 step faster than usual on the time table.
Unsettling Form: Your body, which you are so proud of, has been altered to a degree to make normal people battle with nausea on sight. Gain a +1 to Intimidation rolls when using to attack or defend.
Lawbreaker (Second): Gains a +2 bonus to all spellcasting rolls made to transform someone.
Lawbreaker (Fourth): Gain a +1 bonus to all spellcasting rolls made to enthrall another.
Doctor (Surgery)
Powers:
Inhuman Toughness [-2]
Inhuman Recovery [-2]
The Catch [+3] is gross physical trauma; a landslide is still a landslide, a hundred foot fall is still a hundred foot fall.
Channeling: Biomancy
Ritual: Biomancy
Refinement [-3]