In many comic storylines, Kang takes on the role of a timekeeper. His ability to control and manipulate time makes him a significant and complex character.
Kang wasn't typically black in the comics. Usually, his character was presented with other characteristics. However, the comic world is diverse, and there could potentially be an exception I'm not aware of.
Kang's demise in comics is a complex matter. It could be a result of a team-up of heroes, or it might be due to an unexpected turn of events involving multiple characters and their actions.
The identity of who defeats Kang can change from one comic series to another. Sometimes it's a team effort by multiple superheroes, and other times it could be a lone hero with a strategic advantage.