Princess Celestia and Princess Luna. Immortal rulers of Equestria, shepherds of the Sun and Moon, and arguably the most powerful beings in existence.

Even they are not immune to the dreaded rivalry that comes between sisters. Feeling her sister has gone soft over the millenia spent alone, Princess Luna challenges Princess Celestia to the one and only Iron Pony Competition.

Which sister will come out on top?

Now with fanart! By Soulite1110

Princess Celestia takes a moment on her birthday to recall the cakes she has eaten and the memories they elicit.

Now featured on Equestria Daily and Las Pegasus Tribune.

Edited by: PropdowPony
Princess Celestia With Cake used with Ric-M's permission

After Queen Rarity once more rejects the advances of one of the many noble ponies who seek her affection, Princess Sweetie Belle finds out that her sister is secretly in-love with somepony else, thus her heart-breaking streak. Alone in the throne room with her sister and the royal body guard, Twilight Sparkle, the young princess decides that she's going to find out the identity of Rarity's secret crush, no matter what.

Part of the Bodyguard!AU Series, based on Earthsong9405's AU where Twilight is the bodyguard to a "Princess/Queen Rarity". Prior knowledge of the AU is not necessary to read the story.

When Starlight Glimmer decided to play with time, she created worlds that never should have been. Now she goes to a young Twilight Sparkle, to give her the tools to end the war with Sombra.

She can only hope the Twilight in this world can forgive her for it.

Editing by: m1ntf4n

Ever since Tirek had been returned to Tartarus, Celestia has been experiencing a recurring nightmare: Luna was never healed and she was only biding her time. Celestia wakes every morning covered in cold sweat and yet she knows the dream is impossible. Luna is only Luna. So why? Why can she not rid herself of these horrible images? Luna suggests a plan to vanquish the nightmare knowing it would be impossible in the dream realm. The only possible way: An old spell.
Luna and Celestia are willing to do anything for one another. Does that include becoming the other?

100% Approved by Twilight's library!
100% Approved by Luna's library!

Twilight is just going about her business when she comes across Owen Jones, local human.

His circumstances contrive to make her day unusual and tiresome.

This story is a sequel to Good For Nearly All Princess Labor, Public And Private

Part of getting Equestria used to having the full Diarchy in place is making Luna's presence into a normal aspect of everyday life. And since few things are more everyday than commerce, that means it's finally time to get her visage back onto the nation's currency. All the palace has to do is commission one of the realm's greatest (and most disconnected) artists, and then...

...actually, that was the first mistake.

((Part of the Triptych Continuum, which has its own TVTropes page and FIMFiction group: new members and trope edits welcome. This story can be read on its own: it just happens to take place after the events of the linked piece. No reading or knowledge of that earlier story is required.)

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This story is a sequel to Scion of Chaos

After returning to Ponyville from Canterlot, Sweetie Belle tries her best to find her place amongst friends and family and to remember what it feels like to be home.

This story takes place 4 days after the finale of Scion of Chaos. (I recommend reading that first, if you haven't already)
And set 5 years later is the sequel story: A Heart of Change

Thanks to Rameslack for his amazing cover art.

Hitch doesn't really like change. It used to be that if tomorrow wound up pretty much the same as today, with forensic analysis needed to distinguish either from the day before... then that meant he'd done his job. The peace had been kept.

And now everything has changed. There are pegasi and unicorns in Maretime Bay, some of whom seem to believe that they've brought their own laws with them. The task of keeping those interactions from becoming explosive is being pressed between the hooves of one stallion. A decidedly harried, extremely overworked stallion who doesn't like change, happens to be raising a baby dragon on the side, and doesn't understand the other two cultures at all.

Hitch is tired. That's probably not going to change any time soon.

Now with author Patreon, SubscribeStar, and Ko-Fi pages.

Based on the image, by Equestria-prevails on Deviantart. Two guards, one Day and one Night, having a drink on their night off.
This more or less came about when I wondered at the backstory of the image, saw several other people doing the same, then decided to make it happen.