Wanted to give Luke Cage more of a melee mercenary look, because that what he essentially is (hero for hire = mercenary).
Carl Lucas was always two things: A fighter and a hustler. He made his money the best way he knew how: his fists. He described his lifestyle "I'm not dumb, it's just that being smart aint good enough. Not down here. You gotta be tough, and you gotta be clever. If you not, well you better fast!"
He worked the streets as an enforcer, a job he hated, "I wasn't lookin' to hurt nobody, but it put bread on the table, and kept the lights on." Unfortunately the gang Lucas was working for fell out of favor with some of the "higher ups." A disgruntled friend sold him out, to save himself. "Things went down, and I was the last one standing, so they had to put me away."
"While I was inside I had a lot of time to think, I didn't really do too much of that, not with my hands anyway, and it cost me. People go inside and find God or Muhammad, and that's good, (My Big Mamma [maternal grandmother] raised me to respect God), I found myself. I knew I had to better myself." And that's what he did. This didn't go unnoticed.
Due to his latent mutant DNA being discovered by the warden, Lucas was granted a "parole opportunity." "They said I could be the next Captain America, and I was like 'Sweet Christmas!' I got a second chance. Those a rare gifts from where I'm from."
He was experimented on and exceeded everyone's expectations and was paroled as promised. Unfortunately his new employers were not as noble as they presented themselves, and he broke away from them, and started to become "his own man"
"It was like a rebirth for me. I changed my name and everything. Now I'm Luke Cage, 'Power Man, Hero for Hire."
He started indepetly for a few years because he now has trust issues. But eventually he started a partner with Danny Rand that eventually grew into his own small underground borderline illegal business of fighting crime for pay. He eventually recruited Misty Knight and others. Cage also partners with Daredevil, and Moon Knight from time to time.
Eventually SHIELD comes into play later. Nick Fury (the black one) wanted to recruit Cage, but Cage refused because he doesn't trust the government, and big organizations. But Nick Fury told him how he got his powers (the same way Luke Cage did) and the two started to relate to each other.
But working for SHIELD meant that he had to change his appearance to a more uniform, professional look (as opposed to street clothes). This is an idea of what that look would look like.
[edit: 3/31/2012 numbered designs]
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