Star Trek

I've listed them in alphabetical order

Female changling,  because she's creepy. But again the best villain of them all is Dukat

My favourite villian from Deep Space Nine will always be Gul Dukat!

You forgot Kai Winn, I always thought of that pyschotic b!*%$ as the most manipulative and self-centered character in Star Trek. However, Dukat takes the cake for me, maybe its the fact that he had more screen time and he managed to become the enemy of every character on DS9...

Sisko - a little obvious, in many ways as much as a Sisko was the reluctant hero/emissary throughout the series, Dukat was the reluctant villain. classic good/evil dynamic... watch "Waltz" for reference

Kira - despite Kira's momentary lapse in judgement midway through the series (season 4 "Indiscretion" & "Return to Grace"), having apparently almost forgiven Dukat for his past transgressions against her people; Dukat still managed to piss Kira off.

Jadzia/Ezri Dax - well what more can be said than, he killed Jadzia?

Worf - Dukat killed the love of his life, too bad Worf never had the opportunity to face Dukat himself.

Garak -  once Dukat he became the head of the Cardassian government in Season 5 "By Inferno's Light" he ordered Garak's execution. Also the two had a long history, which was never fully explained.

O'Brien, Bashir, Jake, Odo, Quark - I guess their hatred for Dukat would stem from the murder of Jadzia.

Gul Ducat. He killed Jadzia, I Loved that Woman.

My mistake..Kai Wynn was a real pain in the a%$! It's a shame I forgot her

Simple and to the point; you must have been desperate in your un reciprocated love 

Of the characters listed, Garak's my favorite. But Dukat was the best villain. 

Gul Ducat, no question.

Kai Wynn was definitely NOT my favorite, but isn't that really the point of a villan--to hate them?  I think she'd just barely eek out ahead of Dukat as the best villan, only because she was supposed to be a good guy but was so damned deceitful.  At least you knew when Dukat was lying.

Now, my favorite: I'm going to say Damar--because he's the Cardie equivelant of O'Brien.  He is the perfect Cardassian soldier.  He hates Bajorans because he is Cardassian.  He followed Dukat in a one-ship klingon war because he was a soldier and Dukat was his superior. He supported Cardassia's entry into the Dominion because they promised Cardassia's rise to it's former glory.  He rose up against the Dominion because he loved Cardassia.  Damar is what it means to be Cardassian!

FOR CARDASSIA!

I like how you see Damar. At first, I thought he was nothing but a jerk, following Dukat blindly like a pubbet; not seeing a bit the egoistic manipulative schemist hidden beyond the not-so-successfull mascquerade of patriotism...But then, he started to make sense when I started to see him as a plain soldier who plainly loved his home beyond any considerations of morality or ethical concerns. His character grew and got tempered with his involvement with the dominion, and his personal trials and inner conflict made him a believable and likable character.

As for Kai Wynn, I think she's one of the all-time memorable villains who deserves a place among the best in the history of villainy. She was an evil  bit$$ who did not realize she was one; and -like Dukat- she was a self-deluded mad person who thought they were doing their world a great service; this is the essence of what makes them both great villains

Weyoun loved his character, very charismatic ,sarcasstic, odd humor and the fact that if he would die there would be another ready to go. And i loved his blind devotion and undying love of the founders. 

He was the one who made the Vorta worth watching. I loved his twisted diplomacy.

Ducat is not only my favourite DS9 villain, but one of my favourite Star Trek characters ever. He always made the show more interesting.