Real Name: Duane Alexander
AKA: Yuri
Actor: Lennie James (using his American accent), Ref:Jericho+"John," Person of Interest

Concept

Wisened, Hard-Core, Veteran Troubleshooter

Tropes

Cool and serious; doesn't raise his voice, and doesn't kid around.
No problems with killing bad people, cutting off thumbs, staging an improv robbery, torturing gov't officials, or whatever it takes. Will totally knee-cap everyone if he's in a rush, or ordered not to kill anyone.
Smoothly and unapologetically deceptive in his dealings with non-Project persons; always has a backup story, and it's rarely/never true. ("Becomes" whatever is needed by the situation.)
Extremely loyal to the Project, and Gabriel. Eventually stopped trying to uncover who Gabriel is.
"Knows where the bodies are buried," but reveals only what is needed when it's needed.
"His superpower is an unflinching resolve."

Yuri's true background and motives are shrouded in mystery. The only person (in the campaign) that knows his real background or identity is Gabriel.

Possible military experience (Spec Ops)
At some point, joins the CIA as a Paramilitary Operations Officer in the Special Activities Division (SAD) of CIA's National Clandestine Service (NCS).
Burned at CIA; on the run, effectively homeless
Recruited by "Gabriel," acting as a troubleshooter/investigator/man-on-the-ground in cases against white-collar criminal operations; designated Project Proteus.

B&E; Deception; Marksmanship; Hand-to-Hand Combat; Tactics; Espionage; Interrogation; Indomitable Will

This character isn't an Ally to Raphael D'Angelo, in game terms, but a function of Gabriel's "assistance" (as a Patron)—if the Patron assistance roll succeeds, he may send Yuri to help.
He's "The Wolf."
Off-screen, it's assumed he's working other cases or gathering intel. May show up having just left some nefarious activity; hear suspicious noises in the background when on the phone; etc.

"It's the fear of torture that gets results. Actual torture...only works in the movies."
Very much like Denzel's Equalizer when he was on the job

Basically a combination of John-Person of Interest and Hawkins-Jericho—with maybe some Human Target or Pretender.
The original basis for this character was a super/mutant, an animal-based shapeshifter (like Manimal) codenamed Proteus, who was also a government agent.