Oh man, toss up between Anton Chigurh and Lalo Salamanca. I think Anton is the more frightening of the two due to how realistic of a portrayal he is, but Lalo is definitely the most entertaining.
I love both Anton Chigurh and Lalo and think they’re both really great psychopathic villains. Even though Anton Chigurh is a better villain and more of a psychopath than Lalo. Todd is also a good representation of a psychopath I guess.