#9 - Pagan Gods
Antagonists are even better when their work makes them happy. That's especially true for the Pagan Gods turned over-the-top suburbanites in "A Very Supernatural Christmas." Only the warped minds of the Supernatural creative team could pull off such this absurd pairing. 
Meet Madge and Edward Carrigan, the modern day too-sugary- to-be-real elder couple next door. They're straight out of a 1950's sitcom, except they're more like Ozzie and Harriet meet Alfred Hitchcock. Edward comes complete with the Robert Young cardigan and pipe, and Madge and her plastic covered couch has issues with bad language in her home, especially from the victims she's slicing open.
So what happens to centuries old deities when times change and their way of life is compromised? Most just die off or get killed, but not these two. They're the rare breed that chose to go with the flow and assimilate into normal society. They're the happiest mass murders you'll ever meet this side of The Joker. 
Not only are they jubilant over partaking in all the traditional holiday rituals that go into eating humans, like dragging victims up the chimney while still alive and ripping out whole fingernails and teeth while the victims wear meadowsweet leaves (after all, nothing else smells finer), but they have every hideous Christmas decoration imaginable on display to show just how ridiculously happy they are.   As I've always said, go large or don't go at all. 
I'm not sure what I loved more, sweet and portly Madge holding with ease ginormous Sam against a wall by the throat, or her getting Dean to use the word "fudge" while putting him through painful arm slicing torture. Or how about the fact that Pagans also hate fruit cake?
In the end, it was their love of tradition that led to their downfall. Considering Pagan Gods are killed by a wooden stake through the heart, the live Christmas tree became a convenient Winchester weapon.   I bet other Pagan Gods didn't have that trouble when hunters tore apart their fake trees.  


#8 - Casey The Demon
Casey made only one appearance, in season three's "Sin City," but man did she leave an impression. Forget the fact her hot looks reel in both hapless hunter Richie (another "what were they thinking" character) and catch Dean's attention as well (strange considering Sam has the thing for brunettes). It's her sassy and sardonic attitude that makes her so much fun to watch. Plus, her and Dean really did have some chemistry going.
The best moment by far is the long conversation Casey and Dean had while trapped in her lair (aka, basement). Casey is caught by Dean in a devil's trap, but that doesn't stop her. She uses her demon mojo to create a mighty wind that destroys Dean’s book with the exorcism spell and causes the cave in that traps them. â€œYou lousy bitch, you’re still trapped,” Dean says in reaction. Casey doesn’t miss a beat. â€œSo are you, bitch.” 
Ah, but it gets even better from there. After Dean can’t recite the proper exorcism from memory, Casey gets to rub it in. â€œNice try, but I think you just ordered a pizza.” This kicks off their long, candid conversation in which Dean slowly warms up to her. After all, Dean is about hearing it straight and everything Casey says makes a lot of sense to him. It also helps that both have an enticing spark between them. 
So what does Dean learn from all this? That with Casey's simple, easy and logical approach to human conquest, by catering the moral depravity of man in general, the human race is pretty much dooming itself. He also gets to see the other side of faith and finds Casey's unwavering loyalty for Lucifer no more irrational than those that believe in God.   She earns his respect enough where he asks her about Hell, and finally hears from someone with the proper insight the horrific doom he’s about to face. She’s the one that starts convincing him he's in denial about his fate.

The conversation closes with more troubling news about Sam. Dean listens to all this with a brave face, but we see in his eyes how much what he's hearing hurts.   The yellow eyed demon had a name, Azazel, and Sam was to be his second in command. Now Azazel's death has caused chaos, which doesn't bode well for Sam. Then Casey honestly admits she would have followed Sam. By this time Dean is more smitten with Casey than anything, and sees that some demons aren't that evil after all. 
Of course, none of that matters when Sam barges in with the newly revived colt and coldly blows Casey away before Dean can stop him. That ends up disturbing Dean more than anything Casey did or said. Her memory lingers in Dean, like during his and Sam’s fight in “Malleus Maleficarum.”
The clips of those two together are just too long to show, and one part didn’t stand out over another, so just put on “Sin City” somewhere around the 18 minute mark and enjoy. 

Top Ten Supernatural Antagonists - #10