This one is definitely hard since there are so many villians. I decided that I'd just work with the Buffy villians, as the ones in Angel would make it harder for me to work on! 😛
Best Introduction- The First Evil (admittedly, it sucked after the introduction in Lessens (got crap after CwDP) But you can't say that Cassie's statements weren't chilling in CwDP with Willow. She started off acting so nice and, she was essentially Tara, and then we saw her become the first evil. Chilling stuff and a good show of the First Evil, and then, well, they screwed it up. Rofl.
Best Appearance- Glory - This women was just amazing, the epitome of the villianess, she was pretty much just the head bitch in charge, she didn't care about what anyone else thought, and not to mention she essentially raped Tara's mind and then completely threw off Willow's magic attack. (I consider all of these under appearances, just so you guys know.)
Best Dialogue- The Mayor, Faith, Glory and Drusilla. The Mayor was just eerily hilarious, you knew a lot of what he said was just sick, but it was just funny. Faith had dialogue that was just criminally insane, and it was perfectly acted. Glory was just so glamorous with the way she talked, but with the words that came out of her mouth, she was nothing like it. Where as Dru was just hilariously insane aswell, she had some of the best one liners.
Most Threatening- Glory. Super-bitch, seriously. She absolutely DESTROYED half of the cast at one point or another, and not to mention that she seemed so small yet was insanely amazing.
Best Fights- Faith vs. Buffy in Graduation Day Part 2. The fight was so emotionally charged and shocking that you just had to keep watching to see who won, and it was the sort of fight, that even though the show is Buffy The Vampire Slayer, Faith could've won the fight. And not to mention the ending where Buffy shived Faith and Faith didn't let Buffy have what she came for, was just perfectly done. (Honorable mention was the final fight, only because it was so very well done, Buffy's conversation with her self, Willow, Anya's sad death, which was done so well, and just the awesomeness of the fight xD)
Worst Introduction- The Annointed One (Need I say more?)
Worst Dialogue- The Annointed One
Worst Apperarance-The Annointed One
Least Threatening-The Annointed One, he was just a little kid!
Worst Fights- The Master vs. Buffy.
Punch! Punch! Punch! *The Master is dead*
Like wut.
But yeah, definitely hard to rank, but Glory, Faith and The Mayor were definitely some of the best villians, of course, Spike, Angelus and Drusilla are up there as honorable mentions, Angelus imo made his mark though when he killed Jenny, and really didn't do anything too big after that which made him seem hugely villiany.