One of the points I highlighted in the post about the heel-face turn is that these turns lend easily to black-and-white morality and that’s a problem because we don’t live in a world of black-and-white morality and neither should your characters. Life is never that simple and if you’re writing it as such, you’re being lazy. Of course, there’s a time and a place for your paladins and your monsters but if it’s all white or black, we have a problem.
Why might a good guy turn sour? Again, I think that you could think of reasons on your own, or just read the TV tropes page. There’s no need for me to repeat here, even if in more detail, although I’ll boil the reasons down for you later. And again, if your hero turns, it has to matter, it cannot merely be a simple erasing of alignment on a character sheet as the DM points out that you’re not chaotic neutral but “evil and a whore”.
We’re talking about a complete change of personal philosophy here and something like that is hard to come by so make it count! Think about how hard it is to even change your own mind about something. Take your political stances, for example. Liberal, Republican, Libertarian, Two-Party Politics Are Stupid Screw Your Houses I’m My Own Thing – if you encounter someone who has pretty different views than yourself, and how likely you are to get them to change their mind, or they to change yours. Especially in this day of yelling at people on the internet where actual argument has mostly been lost (sigh). What’s your stance on abortion? Uh-huh, and how many arguments have you been in where the most convincing arguments about the person-state of a fetus, the rights and responsibilities of a woman, and whatever else were presented? And how many times have you left with the same view anyway? That’s a personal philosophy. It’s not easy to change.
Thus the problem of a face-heel turn – and a heel-face turn, yes, although I think because people usually at least want to be good, it’s easier to go good than bad unless what’s what is very unclear. Which, then again, it usually is. Either way, the idea is that a person is at least trying their hardest to be good and then decides they just don’t care anymore, for whatever reason, has a change of heart (it’s not a turn, either way, if there’s not a change of heart) and rides the opposite way.
So the reasons – you can boil them down to either the hero got tired and gave up or he was corrupted. The former reason has an excellent example in the idea that “you either die a hero or live long enough to see yourself become the villain”:
Of course, just giving up is not quite right as that indicates, to use DnD terms, more of a slide from good or lawful to neutral. So make sure if you’re heroine is “just giving up” she’s “just giving up” all the way into actively doing wrong because what the hey. Who cares? No one’s good anyway. Or whatever.
There is one important aspect of turning evil I want to address that shows up in visual media and that’s the evil makeover. It’s that the evil makeover is really gimmicky and I hope that you don’t do it. Well, that’s not true: I hope you don’t do it stupidly, especially if we’re talking the most gimmicky of it all, the evil costume swap. It’s one thing if you have, I dunno, some little Catholic school girl who says “screw this” and wears the clothes she’s always wanted to wear, the way a girl might actually do it.
But putting your character into “evil clothes” just because you have to visually identify them as evil?
Just please…don’t. The only people I know who dress a certain way because “that’s how [X thing I want to be] dress” are people who don’t know how to actually BE X, and they’re often teenagers or clueless midlife-crises “old” folk. It’s shallow, and it’s really pathetic. Besides that, I think a lot of the clothes in which women find themselves stuck are really stupid.
Another thing I want to address is what, exactly, it means to go evil. If the character is trying, especially if they’re trying too hard, it’s not really going evil, is it? Going evil should be natural – again, it’s a change of heart, so it’s just letting go of things that mattered. Regardless of whether or not it’s giving up or becoming corrupted, barriers against evil acts are worn away all the same. Thievery? “Everyone steals so why does it matter, it’s about time I got what I wanted” and “To get what I want I have to steal and I’ve decided what I want is more important than anything else” – a giving up and a corruption example each – are both the same death of a value.
But remember that just because someone does a face-heel turn does not mean that they are now going to become the essence of everything bad. Because morality is not actually black and white, your character may decide he doesn’t care about not being a jerk, but still wouldn’t kill someone. Maybe he’ll eventually get to the point where he might kill someone, but getting to the point where you could kill is a pretty big leap. Your hero shouldn’t have been someone who was perfect at everything good so why in the name of Satan’s second cousin would they become perfectly evil with a turn? So when you do a face-heel, take careful note of just exactly what drove your character to this, how far-reaching and long-lasting the effects are, if he’s fallen and can’t get up or will continue to fall, and gauge carefully just what he will and will not do now that he’s evil. Going from decent enough of a guy (or better!) to an anything-goes bad guy without good enough reason is lazy.