Over the course of Supernatural's 14-season run, Dean (Jensen Ackles) and Sam (Jared Padalecki) have seen their fair share of strange situations. From vampires targeting Twilight fans to a pagan god masquerading as an heiress, they've been through everything on the long-running CW series. Well, almost everything.

Last season, the show entered weird new territory when it crossed over with the animated classic Scooby-Doo in one of its most mind-boggling episodes to date. That unforgettable adventure saw the Winchester brothers transported into a whimsical 2-D world, where they came face to face with the iconic Scooby gang, after receiving a free TV set. And in Season 14's "Mint Condition," Supernatural tapped into its horror roots with a fresh, fun installment that saw Sam and Dean take on action figures brought to life, further proving this series still has plenty of creative juice left in it.

As we approach the show's monumental 300th installment, we're taking a look back at all the Supernatural episodes that made you scratch your head and wonder, "What the heck did I just watch?" Check out our ranking of the 10 most delightfully bizarre Supernatural episodes ever and see where the likes of "Mystery Spot" and "Scoobynatural" fit in!

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10. "A Very Supernatural Christmas" (Season 3, Episode 8) In a creepy twist on a festive holiday, the Winchesters investigate the strange disappearances of townsfolk who were snatched up their chimneys by a mysterious creature. While it didn't exactly ruin Christmas forever, the odd case did make us think twice about waiting for Santa by the fireplace.

9. "Slumber Party" (Season 9, Episode 4) If you're still trying to wrap your head around this one, you're not the only one. Things go off the rails when Sam and Dean find an ancient computer that opens a literal door to the world wide web. Inside, Dorothy from The Wizard of Oz has trapped herself and the Wicked Witch in an effort to stop the evil sorceress from using a key that would connect our world to Oz. Yeah, this definitely wasn't the Oz from your childhood.

8. "Plucky Pennywhistle's Magical Menagerie" (Season 7, Episode 14) Clowns are creepy enough on their own. Clowns manifested from your worst nightmare who end up murdering your parents in the middle of the night? Downright terrifying. However, the campy tone made this episode not so much frightening as it was just... baffling. But that's not necessarily a bad thing.

7. "Fallen Idols" (Season 5, Episode 5) In an episode that can only be described as Hollyweird, Sam and Deam went toe-to-toe with Paris Hilton — err, a pagan god who assumed her identity in order to feed off her adoring fans. While the oddball case didn't contain as many twists and turns as we'd hoped, seeing the hotel heiress perform human sacrifices was both strange and wildly entertaining.

6. "Mint Condition" (Season 14, Episode 4)
Just when you think you've got this wonderful show about demon-hunting brothers pegged, it somehow finds interesting new ways to surprise. In "Mint Condition," Sam and Dean battled creepy action figures that were being possessed by restless spirits, delivering a boldly fun hour that juxtaposed chilling terror with slapstick comedy. The thrilling story also paid homage to the show's horror roots with sweet little nods to "Route 666" and "Hell House," capping off a truly delightful episode.

Supernatural's Jensen Ackles and Jared Padalecki Tease 300th Episode

5. "Changing Channels" (Season 5, Episode 8)
No one has had more fun with the Winchesters than the Trickster, the archangel who has transported the brothers to alternate universes on numerous occasions. This time, he sent them to a different reality in which they are characters in a series of television shows. But hanging out in the sleek Grey's Anatomy-esque medical drama Dr. Sexy, M.D. sounds fun until you realize you could be trapped there forever.

4. "Just My Imagination" (Season 11, Episode 8)
You know you've got a doozy on your hands when Sam's imaginary childhood friend appearing isn't the strangest part of the episode. The episode centers on a woman seeking revenge for the death of her sister, sparking a murder spree of invisible creatures that forces the Winchesters to take action. Sadly, the Winchesters are too late to save Sparkle, a glittery unicorn man, who meets a brutal end when he's stabbed in the chest with a dagger.

3. "The French Mistake" (Season 6, Episode 15)
Sam and Dean are no strangers to alternate worlds but this one — in which they're actors on a TV show called Supernatural — was truly bizarre in the best way possible. Featuring callbacks to the stars' real lives and several scenes that blurred the lines between fiction and reality, this meta episode stands as one of the show's most unforgettable installments to date.

2. "Mystery Spot" (Season 3, Episode 11)
Dean has kicked the bucket more than a hundred times on Supernatural and most of those deaths can be attributed to this single episode. In the Trickster's first appearance, Sam was forced to relive the same day over and over, with the day only restarting after Dean's unfortunate passing due to some truly creative means, including getting a piano dropped on him and bad tacos.

1. "Scoobynatural" (Season 13 Episode 16)
The boys got animated in Supernatural's most ambitious episode to date. When an old TV transported Sam and Dean into the world of Scooby-Doo, we were met with a fun-filled mystery for the ages. Positioning our beloved demon hunters alongside the wholesome Scooby gang could have been a tonal serious misfire, but Supernatural perfectly blended their own unique wit with Scooby's classic hijinks and proved that even 13 seasons in, Supernatural still has so many more incredible (and wonderfully weird) stories to tell.

Supernatural airs Thursdays at 8/7c on The CW.

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