While hanging out on Hearts and Hooves Day, Spike and Big Mac discussed how the Mane 6 had run off to parts unknown during the more recent Hearts and Hooves Days, including this one. Big Mac asked Granny Smith if she knew anything, but the elder pony claimed to be sworn to secrecy and told him to drop the matter.
Naturally, being denied just made Spike and Big Mac yearn to learn the Mane 6's secret more. Overcome by curiosity, the pony and dragon defied Granny Smith's order and set out to learn what their friends and sisters were up to.
Spoiler alert: you didn't really think a hint to the Mane 6's secret would be here, did you? Har har, har-ly har har!
Chapters (1)
Hmm... Well, that was certainly a thing that happened (However much Spike and 'Little' Mac wished it didn't
)
I'd be interested in seeing the follow up awkwardness when the girls sober up and realize what happened.
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Saying they wished it didn't happen would be an understatement
And following up on the fallout after (especially) Applejack and Twilight became sober is something I can keep in mind.