But what are Martians?Nah because right after Aquaman does that, Martian Manhunter appears and goes "Yeah bitches, Martians are real and we are fucking scary."
Doesn't the audience need to understand that first? We haven't been to Mars. I'm not even sure half the audience knows there is any other planet apart from Earth. I think we'd have to spend a decent amount of time explaining the origin of Martians and how Mars fits into the Milky Way galaxy. After that science lesson, we can move onto the character and his own personal life story.
Maybe talk about his first love (Batman) or how he's trying to live properly in an improper world.