i got it roughly around 30 min played in Fort Joy

Got it for mercy killing a dude in a dungeon.

I got it after revealing Stingtail as the orange thief to Griff.

I am trying my best to get this tag but failing to do so. I murdered many people in fort joy, couldn't reveal stingtail because sebille already killed him. I try to always answer in a menacing way in dialogues. Enslaved Lady vengeance still didn't get it. I tried to just straight up murder the meistr after freeing her, also didn't get me the villain tag. I am doing most quests optimally for most exp and then kill the people afterwards but somehow it doesn't seem to work.

I got mine by being evil during starting phase, i pick pocketed the other origins characters and got to unnis. Tried to manipulate her but failed so i had to kill her. Than at the entrance i sided with Griff's men and killed elodi and right after that took on imprisoned elf quest and ratted stingtail and got the tag. From here on out i'll be good, i promise (hopefully the tag won't disappear)

If you consume the Ghost Dogs Spirit in Stonegarde, i think you get an instant Villian , dont eat Dog Spirits though

If you follow the quest The Teleporter for Gawin, way down on the beach you teleport him over there is a dead elf with a purple pouch on her. Bring it to another elf (also near the secret path Gawin leads you through up on the ridge to the left instead of the right) and you can handle the dialogue in a way that earns you the Villian Tag. You can get this very quickly then earn Hero by following that mad man quest line on the beach in Fort Joy and have both tag options available all game.

This***** is so broken. I did everything on this list + more and haven't gotten it. If you don't do a couple of *very* specific "evil" acts in the very beginning of Act 1, the amount of evil you need to do to "make up" for it is completely imbalanced.

It is "VILLAIN", not "VILLIAN"

Another way is to kill the fire slug princess AFTER telling her Braccus Rex is dead(pet pal). The battle log will end with fire slug was murdered in cold blood. This will proc the villain counter.