Mr. Fixer as Black Fist?

So on the character bio page under first appearance it lists two comics with one first appearance as Mr. Fixer but the other as Black Fist.

What's the story there? He's been a superhero multiple times? He was affiliated with some group and had a code name? He had a nickname given by someone else until they actually met him and learned what he calls himself?

Promo card?

A promo card would be cool. But maybe it's just the first alias he used.

The name "Black Fist" totally sounds like his first appearance was in a 70s blaxsploitation-style comic. Which I'm 90% sure was the intention.

Kinda like Black Dynamite?

Yeah, but not as a parody.

Think Luke Cage/Power Man, rather than Black Dynamite.

 

IMO he is more like CreamCorn