It's difficult to pick a favorite character of all the Megaman universes, but, if I were to pick one, it would definitely be Bass. While the other robots and scientists mostly just fill out their roles, Bass is more than simply an evil robot, or a warrior that wants to prove his skill. His first appeal is that he's truly over-confident. He knows that Megaman was the strongest known robot, and he is a better version. But he's also very deep. He's beaten time and again, but this only drives him harder to prove he really is the better robot. At the same time, he's trying to prove that he's more than simply a copy. He claims he's proving that he's "the strongest", but in reality, all he wants to prove is that he's "stronger than Rock", even if he doesn't know it himself. He just wants to feel unique.