Iron Fist is one of Marvel's premier martial arts characters, boasting skills and technique that effective grant him super-powers (such as the technique that gives him his name). His costume is very cool and is far from being a traditional martial arts outfit - but, of course, he is far from being a traditional martial artist. He wears a green gi with yellow trim which exposes his rippled torso and dragon tattoo. He wears yellow plimsolls and a long yellow belt, as well as a yellow bandanna with black trim that covers his eyes. Essentially, far from being either a traditional superhero outfit or martial arts outfit, Iron Fist's costume merges the two and the outcome is very cool.
