My Little Pony: Equestria Girls

Unsolved Selfie Mysteries (5x19)

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Pinkie Pie, Twilight Sparkle, Sunset Shimmer, and Fluttershy take a selfie at the beach, and Twilight notices a black splotch in the photo's background. Sunset and Pinkie believe it to be a sea monster, but Twilight and Fluttershy are more skeptical.