Whatever seems hardest.
Being the bad guy always comes across as easy. Mostly because you're so limited in the ways you can be "evil" by overly simplistic "moral" systems that are far too vulnerable to even inadvertent exploitation.
To use mass effect as an example, all the renegade choices just seem to be the easy ways out. Short term gains for long term losses, etc.
Then to reach back into near complete obscurity, both black and whites (what the hell is pokemans?) allowed you to regularly sacrifice children for mana and still be 100% good. I mean, heres the situation. God simulator. Encourage excessive overpopulation by creating as many "breeders" as you can get your hand on, then scoop up a bunch of kids from the nurseries, murder them for maximum mana, and maintain 100% "good." I mean, while forcing people to "worship" themselves to death (something else that should be pure evil), you can drop tens of living children onto the sacificial altar, directly in front of up to hundreds of people, and they ... cheer... and you maintain perfect alignment... I mean, if my hand, tower, and creature had fully degenerated into the pure evil forms, (black, corrupted, spikey, etc), that would be understandable. Evil people worshiping an evil god and such. But that was never the case... Just another reason that game was lost to obscurity.