Dr. Facilier

Anton Chigurh in my opinion.

I think Anton would’ve maybe qualified if he didn’t shoot that bird, as it was done for no reason at all.

^^Oh yeah, Anton comes really close to being one

Actually being vile is not Anton's actual problem.

It's he's a complete deconstruction of the entire "effing cool nihilistic hitman" trope to show how it's really not and actually is rather pathetic to how hard he tries to cling to such ideals before they get shattered in his face and can only limp his way out of the film.

Oh yeah I forgot about that scene, it was Moss’ wife that destroyed his worldview right?

Personally, I would say the Zombie from Entropy of Vegenance. I personally proposed him myself and he is just barely too vile to count due to lacking a sympathetic or well-intentioned motivation despite the other factors that downplay his crimes. I personally do think he would've counted despite being Pure Evil if he was a genuinely complex character.

TBH I will somewhat disagree on Dahlia Hawthorne, she's able to manipulate people flawlessly sure but the fact she's a failure and even tried to kill her own cousin just to spite Mia Fey for getting her executed, plus the several kick the dog moment of telling Phoenix Wright she hated his guts and taunting him about Maya's supposed death doesn't serve any purpose beyond rubbing salt in the wound, that final breakdown is more the nail in the coffin on her ever having a chance, not really a bad choice in the end though.

To name my own example: Grimmel The Grisly from How To Train Your Dragon 3, not going to bother explaining so only those in the know of Grimmel's history regarding the MB trope can guess LOL.

You see, that's the reason I said "if you make her less arrogant and cruel". She'd never qualify because she's, well, an a**hole. She has the skills of an MB, but not the personality to back it up.

No disagreement there.