She helped them defeat the banshee haunting her home.

Springfield rocked a guitar in his multi-episode arc, parodying himself as a washed-up star reuniting his band Ladyheart.

(That’s when we learnedJensen Ackles' Dean is not a fan of ’80s hair metal.)

“Into The Mystic”

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(Why are ghosts afraid of salt?)

Julie Benz as Layla Rourke

Benzwas the firstBuffyveteran to appear onSupernatural.

She played a Leshii, a shape-shifting god that takes on the form of any object of worship.

Rock Never Dies

Bettina Strauss/The CW

Naturally, the brothers got stuck in the middle.

When she was proven right and the Winchesters saved her life she let them go.

“Did she look familiar to you?”

COLE

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“For some reason, I could really go for some pea soup.”

Mercedes McNab as Lucy

Poor, doomed Lucy.

Nicole “Snooki” Polizzi as Demon

“What’s aSnooki?”

Criss Angel Is A Douche Bag

Michael Courtney/The CW

asked Sam in season 6.

TheMTVreality star nonchalantly appeared after the boys summonsed a crossroads demon.

Actually, she said, “It’s Nicole now.”

SUPERNATURAL

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Fallen Idols

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Shut Up, Dr. Phil

Jack Rowand/The CW

SUPERNATURAL

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Fresh Blood

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Blade Runners

Katie Yu/The CW

Scoobynatural

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