For me, it would be GLaDOS.
Portal 2 spoiler
She deleted the one remaining human part of herself because it was just too much to deal with. She releases you at the end of Portal 2 as a path of least resistance measure because “killing you is hard.”
What about you, what is your favorite media villain?
Favorite Sci-Fi Villain: SHODAN from System Shock/System Shock 2
Favorite Fantasy Villain: The Nothing from Neverending Story
Favorite Bond Villain: Elliot Carver from Tomorrow Never Dies because the writers touched on something quite prescient here about media moguls wanting to control society a la Rupert Murdoch and Mark Zuckerberg.
Favorite Disney-esque Villain: Raphael from Baldur’s Gate III for his “Raphael’s Final Act” song.
Favorite Actual Disney Villain: Lord Hater from Wander Over Yonder
Favorite Action Villain: Hans Gruber from Die Hard
Another vote for SHODAN from me! Founded my love for “Through the looking glass” and everything that followed, like my soul animal, the common Mimic lol