OG Atem would have mind-fucked everybody that got in his way at Duelist Kingdom, except maybe Kaiba. He could have gotten to the castle a lot quicker if he didn't have some honor to his name.
I think OG Atem might even have given Mai a penalty game just for cheating with that perfume trick, lol. Freaky Fish Guy would've been spared that fate due to his honorable nature though.