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Tear Jerker: Cupcakes
Rainbow Dash sobbing "I want to go home."
Likewise, Rarity's final act in life pleading for Pinkie to spare her sister from the same fate moments before death takes her in one of the sequels.
And don't forget yet another alternate ending in which Dashie dies horribly, Pinkie gets backed into one of her murder machines and is ripped apart right in front of Twilight Sparkle, and Twi herself is driven hopelessly insane by it all.
A fan-sequel where Pinkie Pie draws Fluttershy's number has her breaking Fluttershy before setting a single hoof on her—by torturing Angel Bunny and feeding him to Gummy while Fluttershy tearfully pleads for his life.