So, somepony posts a pic and the next pony says another pic and captions the last pic. Example:
P1:*posts pic of the part when fluttershy cries about philomena catching on fire and going into ashes*
P2: Life is sad. *posts other pic*
Aight.
Twilight: Applejack...You are the most non-honest pony I know!
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The sad Vinyl pic.
Ok, I gotta do this one, oh, and this.
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#1. I maked you a bass... but I dropped it.
#2. Never go fishing with Vinyl Scratch. She always drops the bass!
Ok, ok.
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The battle Derpy one.