There are many variety of villains I would like to make:
such as one who has a goal to conquer so much for the sake of greed and glory without realizing what he/she left behind is destruction and slaughter all around and they don't seem to care.
And the other who swore an oath to stay loyal to the villain side to the very end even if it cost them their lives.
Or a villain who like how things go and wants to maintain it, fighting the heroes who are trying to overthrow tyranny and the villains won't allow that.
And of course, a character who seem to be too extreme on his/her actions, something horrific and downright disturbing but there must be a justification on why the villain turned out the way they are, as these words I stay true to it: "No one is born evil, they were just developed to become one".
And lastly, an evil character who manage to achieve his/her goal after all their hard work and would find some slight chance to admire them because of their success and to feel a little sense of sympathy once everything they wanted gets thrown out the window by the protagonists because of the bad things they've done..