Supernatural has featured monsters galore over its 14 seasons on the air. Many of those monsters have popped up more than once. Even some that initially seemed like we’d never see them again, have emerged as major characters in the Winchester brothers' story.

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Yet, Supernatural has also included numerous stand-alone episodes, each with its own monster of the week. Of course, some of those single-shot monsters have been better than others. We sifted through the seasons to determine which creatures land at the top — and bottom — of the list of all the monsters of the week Sam and Dean ever faced.

Here are Supernatural’s 5 Best (and 5 Worst) Monsters of the Week.

WORST: DRAGON (LIKE A VIRGIN)

Supernatural Quiz - Dragons

This season 6 episode was the first and last time fans saw a dragon on Supernatural, and that's definitely for the best. While the episode used sound effects and dialogue to convey how frightening dragons are when they’re in their flying lizard form, we never actually get to see it for ourselves.

Instead, Sam and Dean went up against a couple of guys with glowing hands that we were supposed to believe were dragons who had shape-shifted into human form. It was less than convincing. Plus, the dragons' tendency to steal virgins and hold them captive in a sewer? Yuck!

BEST: GORGON (OUROBOROS)

Fourteen seasons in, it's rare for Supernatural to introduce a monster fans haven’t encountered before. However, that’s just what happened in the recent episode “Ouroboros,” which featured a Gorgon named Noah. Of course, Supernatural's Gorgons aren't like the snake-haired, turning-men-to-stone version of the creature Dean knows from Clash of the Titans.

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Supernatural’s Gorgon was a demigod who paralyzed and ate people. He also saw the future, which is how he repeatedly eluded Sam and Dean. Noah admitted the need to dine on people made for a lonely existence, but at least he had his pet snake. Despite the unpleasant facts of his survival, Noah was strangely charismatic and often oddly polite. As monsters go, he was a mix of scary and sympathetic that made him one of the more compelling recent entries in Supernatural’s canon of creatures.

WORST: VENGEFUL SPIRIT (ROUTE 666)

Route 666 on Supernatural

Technically, the antagonist of this season 1 episode was Cyrus Dorian, a vengeful spirit who was reawakened after decades to take out those responsible for his untimely demise. In life, Cyrus was an unabashed racist who committed horrible crimes against the town’s African American population. As a spirit, Cyrus takes the form of a truck with no driver who systematically runs people of color off the road.

This was Supernatural’s attempt at tackling a serious social issue. The effort was commendable, but the episode’s racist ghost truck was plain cheesy and sucked the resonance out of the social commentary. While many of the vengeful spirits Sam and Dean have hunted since have been genuinely scary, this spirit's revving truck engine failed to strike fear into the hearts of viewers.

BEST: RAKSHASA (EVERYBODY LOVES A CLOWN)

Supernatural Everybody Loves a Clown episode

Supernatural fans know that Sam has a longstanding fear of clowns. And anyone who watched this season 2 episode surely share his phobia now. The official name for the monster the Winchesters were hunting in "Everybody Loves a Clown" was a Rakshasa, a Hindu creature that appears to be human and has a taste for human flesh. They also can only enter a home if they’ve been invited.

The Rakshasa’s basic traits may not have made it the easiest monster to deal with, but it was this particular Rakshasa’s tactics that left an impression. It dressed up like a clown, identified kids with tasty-looking parents at the traveling circus where it lurked, then followed the families home. In the middle of the night, the kids invited the clown into their houses, giving it access to the child’s parents, whom it feasted on. Between the remarkably creepy looking clown and the kids who never learned not to invite strangers into the house, this was a monster of the week that haunted our nightmares.

WORST: BECKY (SEASON SEVEN, TIME FOR A WEDDING)

Supernatural Becky and Sam

Becky may not be the ultimate monster of the week in this episode, but she might as well be. Fans were originally introduced to Supernatural superfan Becky in season 5 when she was just a poorly conceived caricature. She may have been an insult to the show’s devoted fans, but it wasn’t until season 7 that her actions became truly disturbing.

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From the beginning, it was clear that Becky was a Sam girl. In this episode, she took that devotion to the next level when she slipped him an elixir that convinced him he was in love with her. They get married just in time for her to show him off at her high school reunion in a plot that made Becky seem even more out of touch with reality than her previous appearances. While the episode was trying to play the scenario for laughs, Becky holding Sam against his will was gross and the show’s continued ridicule of the fandom through the character was perplexing.

BEST: WEREWOLF (HEART)

Madison asks Sam to shoot and kill her in Supernatural

This season 2 episode was one of the first that showed how heartbreaking Supernatural could be. Sam and Dean come to town to hunt a werewolf. In the process, they meet Madison, the woman who found the creature’s latest victim. Worried that Madison herself could be a target, Sam protects her while Dean goes hunting. During the hours they spend together, Sam and Madison bond and grow close.

When Dean finally tracks down the werewolf though, he realizes it’s Madison. Madison seems to remember nothing about her actions while in wolf form and is terrified when Sam and Dean question her. So the brothers attempt to reverse her condition. Ultimately, they're unsuccessful. By the time they realize they can't help her, Madison has learned that they were right about what she’s become. And she's come to the conclusion that she can't live as a werewolf. Madison begs a bereft Sam to end her life. It’s a tragic stand-alone episode that asks a question Supernatural has often grappled with since: If monsters can’t control their natures, are they truly evil?

WORST: AMAZONS (THE SLICE GIRLS)

The Slice Girls Supernatural

Supernatural isn’t known for its stellar treatment of its female characters, and this season 7 episode showcased all the series’ worst impulses. The brothers catch a case that leads them to a tribe of Amazons. Instead of the strong mythological female warriors we’ve grown to expect however, these Amazons came off as a creepy cult who make their youngest members ritualistically take out their own fathers.

Between Dean lying to get into a woman’s pants, an accelerated pregnancy, and Sam taking down his own niece, the episode didn’t work on any level. And Sam using the Amazons as an object lesson in why all monsters need to be put down made things even worse.

BEST: CHANGELING (THE KIDS ARE ALRIGHT)

Changeling Child, Supernatural

Creepy kids are a hallmark of horror and Supernatural has seen its fair share of them. One of the creepiest examples was the changelings who appeared in this season 3 episode. These creatures took the place of a family’s child. While they looked just like the original kid, their reflections showed what they really were: hollow-eyed, round-mouthed monsters with dozens of pointy teeth.

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The changelings fed off the mother of the child they replaced, slowly weakening her over time. While that would be bad enough, the true horror comes from the mother’s realization that the child in her house is not actually hers. The whole idea of the changelings became increasingly unsettling as the episode continued.

WORST: BUGS (BUGS)

Supernatural Bugs CGI

There aren’t many people who would attest to the awesomeness of bugs. However, "Bugs" took our creepy-crawly fears and tried ratcheting them up to 11. The result was an episode that is largely considered to be Supernatural’s worst. Even the writers mocked the episode in season 4’s “The Monster at the End of This Book.”

The bugs as monster of the week conceit suffered for a couple reasons. Not only is their deadly presence attributed to the well-worn and sadly cliched cursed Native American burial ground trope, the visuals were plain icky. The bugs were supposed to be scary but mostly just grossed us out.

BEST: DJINN (WHAT IS AND WHAT SHOULD NEVER BE)

A Djinn captures Dean and sends him into a dream-like comatose state while draining his blood in Supernatural

This season 2 episode introduced fans to djinn in a story that managed to be equal parts chilling and poignant. Djinn may be more commonly known as genies, but in Supernatural these creatures don’t grant wishes. Instead, they poison their victims, putting them in a comatose state in which they hallucinate their ideal world. Meanwhile, in the real world, the djinn has plenty of time to savor their victims’ blood.

The djinn in this episode captured Dean, and as it slowly drained him, Dean experienced a fantasy in which his mother was still alive. The episode delved into what might have been had Sam and Dean been able to lead normal lives, while giving Dean a limited time to do the seemingly impossible and best the powerful djinn. The episode established just how frightening the djinn were, and also demonstrated why losing one's life at the hands of a djinn might not be the absolute worst way to go.

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