I have this villain. who has a reason to be evil? but like he already was evil and trying to kill our hero before that happens so I need a reason for it. and I got nothing.
the only idea dosent work anyway for the way I want the story to go so I need something else . but I am drawing a blank here. I kinda made him kinda like Grindelwald. wanted to make the magic stand forward instead of hideing. but I decide to make it so the magic world is not hidden but in another dimension
all I got now is he is evil. and I can not create a villain from that. like he is evil that’s it. like he dosent need a full background but he need something I just dont know what
I think we need a little more information about the plot and the roles that the protagonist and the villain play in that plot to come up with a decent motive.
I want to be a king. simple for the reason I want him to live in a castle. the sad part his been evil dosent matter how because his motive is all connected to his new reason for doing what he does that is basically what matters to the plot
also, he cast a spell on himself there made him immortal. they had to lock him in with a spell. and breaking the spell is where the story come start. but I need a reason for him to actually be locked in
I am thinking about just giving him a crappy childhood but like why would he attach the fairys. like I can understand if I made them do something to him but like what
Since he’s immortal, maybe he was unfairly locked away out of fear he’d abuse his immortality. And then, once he gets free, he wants to exact revenge on the people who forced him into solitude despite the lack of ill intentions on his part. That could turn into a really good arc if he eventually learns that exacting revenge turns him into exactly what the people who locked him up feared he would become.
Maybe the elves and fairies have been in a long war with each other and a fairy killed the Evil Elf King’s parents/siblings/close friends and he wants to enact revenge.
Maybe the elf fell in love with a fairy and she broke his heart so now he’s set on getting revenge.
-Me, who sucks at writing villains, comin’ in here to give advice-
So, what we’ve got so far is:
Villain is immortal
Villain was locked away for currently undeveloped reason
Because of MC, villain is now free, and wants to kill MC
From what I understand, the villain currently has a motive, but needs a crime that was committed in the past
I can’t think of anything halfway-good without more context and development and such, but a few basic ideas, take/modify/combine them as you wish:
Poor upbringing (kind of a cop-out but definitely better than nothing)
Trying to hold on to power, irrational fear that someone will/would take it away (maybe he was a fierce dictator, but the people revolted and locked him up)
Species-ist maybe, I guess that ties into poor upbringing
Some “chaotic good” action (he did something that broke the rules and might’ve even harmed society itself, but he did it to protect someone he cared about)
Some revenge, maybe revenge that he already completed so that the new arc can start on a blank slate (ie. someone he cared about was hurt/killed and he overreacted in a terrible way against the killer)
Just simple greed, that’s most of what drives the villains I write lmao
Not every story needs a spectacularly-done villain, as long as the villain has something lol.
You know what would be cool? If the MC was an unreliable narrator and the “bad guy” was actually the good one it is just that the MC’s perspective is so warped
(I am just going to refer to the villain as a he, since I don’t know if it’s a boy or girl)
This might not work with your story because of background information, but…maybe the villain knew one of the hero’s ancestors like a great grandfather or something, and he hated him so he became immortal and vowed to kill his whole family
OR…
Maybe the villain was in love with someone, they were even about to get married, but the villain was poor and weak. They were unable to protect their partner from dangerous criminals, and one day the villain comes home to find his partner dead, at the floor of their home. Since then he vowed to become stronger and avenge his loves death, becoming powerful and immortal in order to protect the weak. The power got to his head, and he turned out lonely and empty which added fuel to his rage.
Here is a simple chart/question sheet that is pretty basic but might help you out. Once you give him a goal it could help with his motivation
Goal : being the most powerful person
Motivation : Thier was a situation where they felt powerless and lost something they valued more than their life. So they vowed to become powerful.
How their actions made them evil: They ruined others simply to gain power and put others in the same situation that they were in.
Realization: They put others in the situation, that they are trying to run from.
Only include the realization if you want your character to be good or redeem themselves in the end
Cough my weird spiraling thoughts
Totally random idea lol
The villain had been locked away for years, his/her thoughts torturing her/him. Everything had been so perfect.
He/She had a husband/wife, a cozy home, and powers that amazed them all. He/She could’ve just lived their happily ever after in peace, but no just because they had to save them. A meaningless family, one that he/she could have just overlooked. But they hadn’t. They had rushed in the fiery blaze and rescued them. Without noticing eyes watching him.
He/She walked home, happiness, that was all they felt as they reached towards the dreaded doorknob. Only to stop in shock and scream in agony when they saw the homes floor flooded with blood.
Then out of the shadows came… the one face they would never forget. The killer
Suddenly the door opened.
The villain’s eyes shot up. Today was his/her lucky day
Most of my loose ideas still stand, though. 
it is just that the MC’s perspective is so warped