Pinkie Cake walked into Mr. and Mrs. Pie's shop because she works there and stuff. Why? Because her stash of thermonuclear weapons party poppers has to be paid off somehow! She slammed the door open with enough force to send it into orbit and land perfectly back on its hinges, which she then opened carefully and sauntered in like the... uh, (proper?) mare she is.
"Pinkie!" Mrs. Pie gasped, "You're just in time for our big summer blowout!"
A pile of poetry-laced clothing-shaped pies and pie accessories pummeled Pinkie Cake to the floor.
"Get 'em!" the pies and pie accessories shrieked, continuing to engulf Pinkie. "She's the imposter! She's SUS!"
As the pies piled onto Pinkie higher and higher, a quiet, soothing voice began to cackle overhead. "YOU FOOLS, YOU THINK YOU CAN DEFEAT ME?"
Everyone, save for three-quarters of a pie and Pinkie's left mane puff froze in space. This, unfortunately, meant that the planet continued on without them, leaving everybody present now floating through the vast voids of outer space as Equestria faded away into a pale blue dot.
And so, with the last remaining ounce of brain cells, the universe proceeded to go boom and die. Again. As always.
yeet