Over the course of seven seasons Buffy the Vampire Slayer, about a teenage girl (Sarah Michelle Gellar) with incredible abilities tasked with protecting her town from the forces of darkness gave comedy, action, and heart. Buffy Summers and her friends faced down a variety of supernatural enemies, her epic battles brought to life by some of the best special effects available in the late '90s.

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Despite the top notch production values, incredibly strong performances from the young cast, and razor sharp dialogue from Joss Whedon and his creative team, the series that used vampires and demons to represent the tribulations of teenage life was plagued by inconsistencies. Here are 10 continuity errors fans didn't notice.

BUFFY'S BIRTHDAY BLUNDERS

Buffy fans find out the birthdate of The Slayer in the first season of the series when her student record is brought up by Moloch. When he sends it from one computer to another, it goes from reading 10/24/80 to 05/06/1979. A few episodes later her tombstone bears a birthdate of 1981, which it would again in Season 5.

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Beginning with Season 2, episodes featuring Buffy's birthday would air in January, which became the accepted birthdate of the Chosen One by fans (01/19/81, for example). Buffy herself solidifies a January birthday be explaining in Season 4 that she's a, "Capricorn, on the cusp of Aquarius."

BUFFY AND HER BOOZING PALS

Buffy Bringing Riley to the Bronze

There are several instances in Season 5 where Buffy and the Scoobies are at The Bronze enjoying rounds of adult beverages. In the episode "Family," they drink at the popular spot to celebrate Tara's birthday, despite the fact that Tara was supposedly only turning 18 (to be fair she isn't depicted as partaking).

However, the rest of the Scoobies aren't necessarily 21. For instance, Buffy was 17 in January of Season 2, which wouldn't make her 21 by the time period of Season 5. Buffy drinking before Season 6 would be illegal, and the Scoobies are roughly around her age, with the exception of Giles.

ANGEL'S MAGICALLY MOVING HAIRLINE

In the exciting two-part finale of Season 2, Giles has been kidnapped and Buffy and the rest of the Scoobies have to prevent hell from swallowing Sunnydale. This results in her having to do battle against her former love Angel who, after their shared night of passion, is no longer bound by the guilt of his years as a merciless killer.

As she battles Angelus in an effort to prevent Acthla's dimension from opening, fans can clearly see his stunt double instead of David Boreanaz by the way his hairline shrinks and recedes about three inches with each swing of his sword.

THE LUNCH LADY'S STUNT DOUBLE

In Season 3, Buffy is given telepathic powers, allowing her to read the thoughts of all the students at Sunnydale High. She learns that one of them suffers from low self-esteem, and plans to bring a gun to school and open fire on anyone who bullied him. Buffy informs the Scoobies and they plan their intervention.

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As it turns out, the student was only intending to kill himself, and the real culprit was a cafeteria worker planning to poison the school's lunch. When Buffy confronts her, she's clearly a large woman, yet the stunt double used to depict her in their fight is a 150 man, instead of a 300 pound woman.

ANYA'S CHANGING SOCIAL SKILLS

Anya hunched over in Buffy the Vampire Slayer

Before joining the Scoobies and beginning a relationship with Xander Harris, Anya had been a Vengeance Demon for 1000 years. This made it seemingly difficult for her to integrate into human society and understand humans on an emotional level, as well as give her a comical sense of tactlesness.

However, when Anya is still a Vengeance Demon and answering Cordelia and Willow's summons, she's perfectly capable of blending in with high school students. It seems Anya's "I don't understand humans" act was only brought about for comic relief or to segue into a monologue about the mortality of humankind.

A WILD BOOM MIC IN ITS NATURAL HABITAT

In Season 4, episode 15 when Buffy and the Scoobies begin their investigation for clues about the season's Big Bad Adam, they discover a demon he's strung up in the woods. Just before Buffy sees it, she comes around a tree, and a crew member is clearly visible standing with a boom mic in full view.

This isn't an incident fans have to look hard to see or locate amidst a great deal of shadow. Prior to "This Year's Girl" airing, one would think the editors of the series would catch a whole body shot of a crew member in the middle of the screen, and take the necessary steps to removing it.

THE FIRST'S FIRST APPEARANCE

Buffy the Vampire Slayer Amends Angel David Boreanaz

Every season of Buffy the Vampire Slayer has a Big Bad that's usually dispatched by the end, but some continue to reappear throughout the series. One of these villains was The First, who first showed up in Season 3's "Amends" as Jenny Calendar stroking Angel's hair, who was in fact Giles' lover whom Angel killed.

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However, when The First appears again as the ultimate Big Bad in Season 7, whose armies threaten to wipe out Sunnydale, the Scoobies, and all of the slayer potentials, it's incorporeal. The First is incapable of touching anything, living or inanimate.

OVERLOADED UBERVAMPS

When fans first saw Übervamps, supposedly the strongest vampires known to the Slayer, they witnessed the ancient entities giving her a very hard time. In "Bring on the Night", Buffy isn't even able to dust the Turok-Han, causing them to gain their formidable reputation.

They appeared later in the Shadow Men's vision spelling the impending apocalypse, yet as Season 7 went on, they were increasingly easier to beat. In the first fight involving potentials, activated by Willow to assume the role of Slayers, they're able to dust them, something Buffy couldn't even manage.

THE SLAYER LINE

When explaining about the severity of The First's assault in Season 7, and how the Slayer line works, Buffy mentions that if she dies, one of the potentials could be called upon to become the new Slayer. However, this makes little sense considering Faith is still alive when the events of Season 7 take place.

When Buffy died for the first time in Season 1, Kendra was activated. When she was killed, Faith was activated. Another potential would not have been able to be activated until Faith was killed. To add insult to injury, when Buffy died in Season 5, no new Slayer was called.

SUNNYDALE'S DISAPPEARING COASTLINE

"Chosen" was the final episode of Season 7 and the climactic series finale, which saw The Slayer, the Scoobies, and the potentials fighting for the fate of the world against the First's armies. Spike makes a decisive sacrifice that sways the tide of the war, and the world is saved from the forces of darkness by wiping Sunnydale off the map.

When the giant hole formerly known as Sunnydale is shown at the end of the episode, it appears to be in the middle of the desert. This is incongruous with other episodes of the series, which has depicted Sunnydale to have a coastline (which the Scoobies frequent), as well as docks with ships in them.

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