Diablo Crossover.

The Archangel of Justice destroyed the Worldstone to spare Humanity the corruption Baal infected it with. The force of its death knell shatters Mount Arreat and sends Tyrael hurtling across the endless planes of reality. He falls upon a world untouched by Angel or Demon, far from the sight of the High Heavens. So far, in fact, that he fears he will not be reborn from the Crystal Arch.

Wounded and near death, hope appears in the form of two strange creatures bearing the power of night and day.

Tyrael now faces a time of recovery as his power slowly heals within a body fashioned for him by his saviours. Justice Incarnate tastes for the first time the life of a mortal, and it is a strange, confusing experience .He has been left in the care of one Twilight Sparkle to learn of this world.

After all, where better to find peace and harmony than Ponyville?

Act I - The Root of Evil
Act II - ????????
Act III - ???????
Act IV - ???????

[Cover image used with full permission of the owner. Go on, go have a look at Chagial's stuff.]

It has been several months since the disappearance of Twilight Sparkle..

One night, after watching her sister raise the Moon and set the heavens alight, Princess Celestia begins to bed down for the night, only to be interrupted by portal forming in her room. From out of the portal comes none other than Twilight Sparkle, garbed in strange armor.

Princess Celestia, along with Luna, Cadence, and Shining Armor, are overjoyed by the Element of Magic's return, but are justifiably curious as to where she had been and what she had been doing. And so, Twilight begins her tale. A tale of survival against impossible odds. A tale of a people fighting for the most basic right of all sentient beings. The right to exist.

A slightly more realistic take on the "Human in Equestria" story concept.

... For a given value of "realistic."

Okay, it's barely realistic but it is a hell of a lot of fun...

Now with an image graciously provided by Page Turner, and an audiobook version narrated by multifanficaday and if you prefer it in German, FrankyDoodle has got you covered!

And a TVTropes Page!

Last Featured: 11/26/2019! Thank you so much!

A thousand years is quite the generation gap, so Princess Luna decides she has to get with the times. However, this isn't quite as easy as she thinks it will be...

Cloud Kicker might just have the wildest life of any pony in Equestria. Marvel at the insanity that is her life, and laugh at the suffering of her poor beleaguered best friend, Blossomforth. And maybe, just maybe, there's more to her than just the lovable sex maniac everypony thinks she is.

This is a semi-sequel to "The Incredibly Dense Mind of Rainbow Dash." Not really a proper sequel, since it's focused on Cloud Kicker and Blossomforth instead of Rainbow and Pinkie, but it's in the same continuity. So I guess that makes it a follow-up-side-quel story. Or something. You don't need to have read "The Incredibly Dense Mind of Rainbow Dash" to read or enjoy this, but you ought to read it anyway, just because.

TvTropes Page

The central story of the Winningverse.

We got a tag for Cloud Kicker, but Blossomforth still deserves one too.

[Complete!] When Rarity finds out how little Twilight gets out of the Library, things get out of hand as she decides to take it upon herself to teach Twilight the ropes of dating. As Rarity drags her around, Twilight begins to have a good idea of who she wants to ask out.

Throughout all of history, one concept has kept both the written and spoken word from becoming an unintelligible mess. That concept is that most holy of grounds known by some as "grammar." It sets down rules for language to follow, and keeps it free of distortion.

Yet something is wrong. The rules are failing. And only one pony so much as suspects that something is wrong. Something that goes deeper than a simple appearance of errors. Something that could be an attack on the very root of language itself.

In the wake of the events of "Infernal Machines" and the Nightmare's most pathetic assault on Ponyville yet, Applejack is thrown into an existential crisis, despite her not knowing what the word "existential" means. So when a stranger named Stranger arrives in town, teaching a new way of coupling talent to power using complex machinery, she is quickly suckered in, along with everypony else. Now, it falls to the Most Dependable of Ponies to bring the resulting ruckus down to earth, but can even Applejack's legendary pragmatism stand up to the brain-fizzing horror that is... CONTRAPTIONOLOGY?

Now with a Spanish translation by Spaniard Kiwi!

Twilight becomes alicorn of the stars. This is sort of a problem, because Luna kind of already was alicorn of the stars. Oops!

TV Tropes

Twilight Sparkle may believe in Pinkie Pie's myriad abilities, but when an opportunity to study them from a perspective she never thought possible arises, how can she resist the chance at the understanding she's always truly wanted? More importantly, can Ponyville survive the trade-off necessary for this opportunity?