I have a character who's gonna be written through a transition. He starts off as a "saintly" pastor who's very docile. He's very religious and he clings to his religion because of his horrible drug addicted past. But as I develop the character as he goes through a tale of gods, angels, and demons I want him to regress instead of progress. I want the character to start getting fed up with his passivity and his dissatisfaction with his own life and proceed to drop his beliefs and all hopes of redemption and eventually become a villain himself. A nasty one at that. But would this ruin the appeal of the character? Having him developed for so long only to take him away and make him the antagonist?
I think it could make him really fascinating, as long as you trace his transition carefully and don't just flip his whole character without warning. The best villains are the ones who could be heroes from a different perspective.
I think this sounds like a very promising character idea. I agree however that this shouldn't be a 'sudden' change. Characters, if they are to be believed as real people, are never 'black and white'. We all love to hate villains that remind us, even slightly, of parts of our personalities. Even Hitler loved his own mother! Try not to 'de-humanize' him as he transitions. Keep somethings constant in character. Don't make him 'saintly' to begin with and outright 'evil' to end with. Perhaps he originally regards himself as saintly and then has a sudden realization that he is far from how others perceive him and is growing tired with the constraints of religious life. I think that some event should suddenly happen that leads to an existential crisis in his identity, whereby he comes to understand that he was merely playing a 'role' to fit other peoples expectations that isn't really him. The 'regression' in his character doesn't have to be absolute. He might end up more charming, easy-going and laid-back than he started out, while living a less moral life overall. Give him traits that let the reader feel that he is 'vulnerable' even as he regresses, maybe with a difficult childhood that made him flock to religion rather than out of any genuine belief in the divine that you can reveal later on in the story to remind people that he's a real person with a real past that haunts him and conditions his actions. That's my two cents anyhow. You could have some fun with his character as he 'grows' into himself and becomes steadily more daring, without making him entirely unlikeable.
I have to ask. Is that the end? Like he becomes evil the end? Do we follow him after he becomes evil? Do we switch perspectives? Personally I agree. I think it can work. I just think it is one of those ideas that has a very small margin for error. Villains can be likable. Heck jerks in media can be likable. If the story doesn't end though and we keep following him I assume you want to keep him somewhat likable. Which isn't to say likable has to be positive traits. As mentioned a jerk can be likable. If I don't like him. I don't care to put it simply. Breaking Bad is an example. Neat show. I stopped watching it because I stopped caring. I actually became more interested in someone killing him off. Something I didn't see happening or at least not until the end. So I had no reason to push to the end just for that.
It doesn't ruin the appeal of the character to me - you have the potential for a growing inner conflict for an added dimension.
If he has legitimate reasons for his regression, then I think that could be very interesting. Especially if he is initially conflicted, which he should be - it's not just about becoming fed up but it's about seeing what you once loved in a new light, those emotions of betrayal, regret, wasted time, wasted love, mourning of an ideal, hope that you might be wrong, trying to redeem what's now tarnished and finding that you can't. If you can portray these emotions through his inner conflict, I think it could be a very good story indeed. Another thing to consider - how will his friends and family respond/react? They'll see something's changing in him and will try to talk him back to the faith, or perhaps voice their own doubts about the faith. Will he hide his regression and how? How does he deal with the pressures of staying in the faith because by leaving, he'll disappoint those whom he love? What about all the good that's come out of his faith? Those weren't illusions. How does that make sense in light of what he sees now that makes him doubt and regress?
Does he have to become evil? Can he start out evil, but keeping it a secret? And then his victims start coming out of the woodwork; to begin with, he manages to silence them with his established saintly exterior so that nobody can believe it of him. But then the mud starts to stick.
He has a meth addicted past and he became a violent thief before becoming a pastor. He lost his family and friends because of the drugs and he hides his shameful past as if it didn't exist now. But I don't really like the Dexter angle. He's not a murderer, just horribly lost. And his transition from hero to villain to ??? is still in his quest to find himself.
Here is the big thing to remember, no person, no matter how history views them thinks that they are evil (unless they have some major mental issues). There are many people throughout history that have done truly demented things (Hitler was listed above) but they do not see what they are doing as evil. To make the transition you need to give him a clear motivation including a detailed description of the change in moral code that has led to this major change in character. If you do not do this well, then what you will end up getting a terrible Anakin Skywalker like story from the Star Wars prequels. (so to save his wife and unborn child (twins) anakin turns to the dark side...and then his first act on the dark side is to kill other random children and then try and kill his wife...who's life being saved was his reason for joining the dark side?) It often becomes way to easy to fall into a "well he's evil now, this is what evil people do" trap. In the real world people do not operate like that. Breaking bad was a successful show because it show'd a man turn in desperation to drugs for money, and then fall under the spell of the wealth and power that his empire provided him. Everything he does is to protect that empire. His actions are cruel and in many instances evil, but the underlying reasons behind them are not. This character will be successful if you focus on the "why" of his actions, and not the "what".
