Yes, he’s done a couple of turns as villains like this. On Legends of Tomorrow he plays Damien Darhk, an evil wizard who has tried to kill the heroes on many occasions, but who is also legitimately a loving father who sacrificed himself to save his daughter, even though he was planning multiple double crosses at the same time. But he’s also clearly just having fun being this evil, unpredictable villain.
Al Swearengen, no? Clearly (at least initially) cast as the villain, but some of the best parts of Deadwood show his humanity and working together with the “hero” to solve problems for his town.
Definitely a good candidate. Will kill without hesitation if he feels it’s in his interests, but if it isn’t in his interests, he won’t.
I like to compare his reaction to finding smallpox in the camp to that Bella Union Cocksucker. BUC tried to hide it for fear that it might cut into his profits, while Swiggen called a meeting of the town leaders to plan for quarantine procedures, and put up his own money as a reward for whoever could deliver vaccines to the camp first.
Now that I’ve written that down, I see certain parallels to the last couple of years…
Oh, yes. I think Swearengen’s just as good a candidate as Dukat. Maybe even better.
In what sense is Q a bad guy? Sure, he may be annoying, even dangerous at times, but it’s not as though he ever acts out of malice, and he almost always presses the cosmic reset button after everyone’s learned the lesson du jour.
In what sense is he “likable”? He always annoyed the shit out of me.
Omar Little is the correct answer.
Boyd Crowder gets honorable mention.
Remember the episode where he loses his powers and shows up on the Enterprise because he knows half the galaxy will come looking for him? He was a pretty bad guy.
Different strokes, I suppose. I’ve always loved his character.
Crowley. Crossroads demon. King of Hell. Supernatural.
Still not an act of malice, but even so, one reckless action out of more than a dozen appearances hardly makes one a “bad guy”.
The point of that episode is that he goes to Picard for protection. He’s pissed off so many species that he knows he’ll be hunted as soon as word of his depowering gets out. Hell, the whole reason he got the boot from the Continuum was because of his treatment of mortal races.
“Bad guy” is subjective, I suppose, but this is your thread and I won’t hijack it further. 
Yeah, if the Enterprise had somehow gotten free from the Calamarain, they were but the first of many species that would have been after him.
“Fending off all the races that you’ve insulted would be a full-time mission. That’s not the one I signed up for.” --Commander Riker
But he was a bad guy to all those other species after him, was the point. Alien lives matter!
OK, I see your and @Johnny_Bravo’s point now. Still, having “insulted” people is pretty tame in comparison to rape, murder, genocide, enslavement, and many of the other things that have been mentioned in this thread.
Agreed. Also helps illustrate that people can be monsters while still believing in their own righteousness. That’s way more realistic than a moustache-twirler.
IMO, only if you were hopelessly naïve. Dukat’s inevitable heel turn was always so screamingly telegraphed to me. He had the smirk of the psychopath.
I’m with Boyd Crowder and Al Swearengen. Both of these characters are so, so terrible, and so, so likeable.
I was a Garak fan. I liked his character arc throughout the seasons. The Federation characters were a positive influence on him.
I can’t remember. Did Garak survive the series? I know he helped in the climatic The Battle of Cardassia.