This is an idea I had for crossing over Sin City into the Dresdenverse.
http://en.wikipedia.org/wiki/Sin_CityThe version of Sin City that exists in the Dresdenverse has parrallel versions of the characters in the series.
The Roark dynasty is a branch of the White Court vampires that feed off of greed. They control the city.
The first "player character" is Marv.
http://en.wikipedia.org/wiki/Marv_(Sin_City). His good friend Dwight tells us that "most people think Marv is crazy. He just had the rotten luck of being born in the wrong century. He'd be right at home on some ancient battlefield swinging an axe into somebody's face. Or in a Roman arena, taking his sword to other gladiators like him."
In the Dresdenverse continuity, this assessment is more accurate than even Dwight might know. Unknown to all, Marv is an amnesiac Einherjar Changeling of the White Court. His father was a Frost Giant. His mother was a Valkrie. The "union" was not consensual. Marv was abandoned and left for dead, but he survived the winter and was found by Vikings who raised him as one of their own. When he came of age, he joined the ranks of their warriors and became one of their most ferocious warriors. Eventually, he fell, and was brought to Valhalla. Unfortunately, his Frost Giant lineage was detected, and he was denied entry to the afterlife. His spirit was supposed to be cast out into the netherealm, but his mother snuck him into Midgard where he was reincarnated. He is literally a lost soul, and ends up in Sin City, deprived of his memories. He's not happy here in Sin City, but at least he belongs...
Marv (10 Refresh, 35 skill points)
High Concept: Lost Einherjar Changeling of the White Court
Trouble: Sometimes I Get Confused
Background: Right at home on some ancient battlefield, swinging an axe into somebody's face.
Rising Conflict: Living on Borrowed Time
Aspect 1: "That's a damn fine coat you're wearing"
Aspect 2: "Is that the best you can do, you pansies?"
Aspect 3: The Hard Goodbye
Skills:
Superb(+5): Endurance, Fists(HtH Melee Wpns)
Great(+4): Athletics, Might
Good(+3): Alertness (+5 vs Surprise and for Initiative), Stealth
Fair(+2): Driving, Guns, Intimidation (+4 to Brush Off)
Average(+1): Contacts, Conviction, Lore, Presence, Survival
Powers:
[-4] Supernatural Toughness
[-2] Inhuman Recovery
[+3] The Catch: Fire & The Trappings of Summer
Stunts:
On My Toes
Paranoid? Probably
No Pain, No Gain
Extensive Training
Lethal Weapon
The Brush Off
Stress:
Physical OOOO[OOOO], 2 extra mild, 2 armor; Mental OOO, Social OOO
Total Refresh Cost: -9