King Crimson is separated from his user and is plopped down in Equestria.

Stupid antics ensue.

A purposefully ridiculous crossover story, which began as a joke and ended in constant, uncontrollable laughter.

Just a crossover of JoJo's Bizarre Adventure and My Little Pony. Nothing special.

In the midst of Twilight's efforts to save the Crystal Empire from Sombra's return, she comes across an ancient artifact hidden away by the dark king. When she accidentally activates it, she brings two strange beings from an entirely different world to Equestria.

A Steven Universe crossover

Uncle lives a very fulfilling life at his antique shop. It's peaceful and quiet for the most part, just how he likes it. Of course, he's a skilled chi wizard, so he knows better than to actually let the universe know that he's content. So he complains.

A lot.

Then one day, a basket containing three infant magical ponies arrives, and his peaceful life goes out the window...to be replaced with, perhaps, something a little more than contentment.

The universe, apparently, is smarter than he gave it credit for, because now he has "Three More Things!" to complain about to hide just how much they mean to him.

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Part of the PWNY-verse.

First chapters take place approximately 10 years before the events of the first episode of the show.

Edit: Cover Art put together by Shadow Bolt
Edit 2: New Cover Art by Swan Song. Link to his page in image source.
Edit 3: Level Dasher commissioned an image of the CMC with their new Cutie Marks from Katakiuchi4U over on Deviantart. Here's the pic!

Ripped from home with no explanation to a place that is both incredibly strange and eerily familiar. What world he walks on, what these creatures are, why he's here. There are many things Rajrishi does not understand about Equestria. He hopes to fix that.

But mostly he just wants to go home.

Twilight Sparkle - magus, heroine and Princess - has learned of worlds overlapping Ungulatia in space and time. Though this has been a well known phenomenon, safely traveling to these other worlds has always eluded pony mages. But now - after years of research and careful experiments - she prepares herself for the most audacious of all experiments: stepping hoof on the surface of an alien world and returning safely! What wonders will she find once she walks through her magic portal?

This assumes that Equestria Girls never happened.

Amethyst and Steven were just enjoying a sunny afternoon outside the Big Donut in Beach City. Never in a million years though would they have expected to find a young...something...in a dumpster. Now seeing that this creature has nowhere to go, the gems decide to take it in and maybe try to find out what the deal is with the little monster's bad case of amnesia, and all the while dealing with the child's extraordinary powers.

Frankly, a child Discord may end up being more trouble than he's worth for the Crystal Gems.

An MLP/Steven Universe Crossover

Trafalgar D. Water Law was a lucky man. Doomed to die at a young age he became a pirate, wishing to only cause misery to those around him. He would eventually become one of the most feared captains on the Grand Line.

It was during his coup against his former leader, Donquixote Doflamingo, that his luck finally ran out.

Fighting a losing battle against the Heavenly Demon, he fell in battle. But, he did not die. No, he instead finds himself in unknown lands surrounded by midget horses and other beasts.

Normally he would approach this situation with the same cold, calculating indifference he usually portrays. He finds himself losing his patience, however, when a creature known as a Changeling decides to follow him around.