This is a fic based on the Time Loop Files, the format of which was first codified by Innortal on fanfiction.net.
Here's a brief guide.
The basic idea is, one character (the Anchor, usually the main character of a fictional setting) is looping back to the very first moments of their parent series every time either they die or some kind of time limit expires. They of course end up monumentally stir crazy given enough time.
Eventually others start to loop as well.
The reset is not always perfect. Sometimes a loop's history will be different to the "prime" loop, or canonical plot.
"Crossover" or "Fusion" loops also occur, randomly. These can involve the home loopers having a guest, or the anchor for one universe spending time in another, or replacements of one character by another.
Vacation Loops are where the Anchor (or others) decide/s "buck it" and lets off steam by doing whatever comes to mind. There's little or no attempt to maintain the original timeline.

In addition, and particularly more recently, it should be known that this story has a collaborative element to it - people may submit loop ideas or loops, ideally at the Spacebattles thread (a link to the current version of which is on the Trope page), and they may become included.

There's two page image options, thanks to Filraen - the current page image has been edited by the original creator from this work of theirs.. The other one is here:
http://hourglass-vectors.deviantart.com/art/MLP-Loops-466030169

UPDATE: 8,000 unique views! Wow! I'm incredibly flattered!

TVTropes Page

Plowpony's Day- a day of peaceful rest and relaxation. Or it was, until Twilight Sparkle badly mangled a teleportation spell. It has left her with a bad case of Horn Rot, a disease that if untreated could prove fatal. What's more, the malady is advancing faster than the slow-brewing potion that cures it!

There is one swifter cure: the Beneviolet, a star-shaped flower that grows in the distant Archback Mountains, far beyond the western borders of Equestria. Applejack, Rainbow Dash, and Rarity choose to undertake the long journey for the sake of their friend. Their path will wind through floes of ice, across gold-tinted plains, into distant forests glimmering with magic. They will learn much about the world beyond their homeland- and much about themselves, as well.

Yes, it's "Dangerous Business," here on FIMFiction. A huge debt is owed to all those who have supported me over the years. I've edited the story some to remove extraneous bolding and italics, but other than that, it remains unchanged. I hope new readers enjoy it as much as old ones did.

TVTropes Page

Humans.

Truth or myth? Ancient lost civilization or just an old pony's tale?

No pony has ever seen one, and most haven't even heard of them. But Lyra knows that these wonderful creatures are more than just old legends, and she's going to find out... and possibly drive her roommate insane in the process.

Sequel to Aperture in my Heart. Chell is lost, and it is up to the ponies to make sure she returns home. However, between Chell and home stands an angry, all-powerful AI, test chambers, and lemons. A ton of lemons.

But no one, not even Space and Wheatley, knows what is waiting for them deep in the bowels of Aperture....

There are many buttons in the TARDIS, most of them should only be pressed by professionals like the Doctor. Derpy, on the other hand, isn't a professional and she pressed a button. The TARDIS crashes into the universe of Minecraft leaving the duo of ponies stranded in the pixelated world with nothing but a broken TARDIS and each other.

Thanks to Lexicon and Minjask for editing!

A diplomatic crisis arises between Equestria and the small, poor kingdom of Tarandroland, ancestral home of the reindeer. Celestia and Luna agree that it is time Luna takes a more active hand in foreign relations again, and Luna brings Twilight with her as someone she actually trusts and can talk to. But the mission turns out to be much more than political discussions - if scheming unicorn courtiers, unfriendly surly reindeer, bloodthirsty pirates, ancient sorcery and dangerous monsters weren't enough, our heroines must deal with something old - older than Luna. And is Luna really ready for diplomatic action, will Twilight learn to use a fan properly, and exactly how wrong are Spike's superhero comics about reindeer mythology?

Now has a TV tropes page