Season 1 Episode 15

"Feeling Pinky Keen"

Twilight learns that the rest of town believes that Pinkie Pie has a "Pinkie Sense", in which her body reacts in different ways as warnings to certain events. Twilight insists that this cannot be possible and attempts to understand how the Pinkie Sense works, though ends up in a number of pratfalls from this. When Pinkie asserts that there's a "doozy" of an event in the nearby bog where Fluttershy is, Twilight, Spike, Pinkie, and Applejack take off to save Fluttershy. They find Fluttershy safe, but are soon chased by a hydra. They all escape safely, but Pinkie asserts that her sense is still going off and the "doozy" has yet to happen. Enraged, Twilight finally relents and gives up on trying to understand the Pinkie Sense; Pinkie's Sense disappears, and Pinkie asserts that Twilight's revelation was the "doozy". Twilight accepts that the Pinkie Sense is real, and that she should stop worrying about its origins.