After several years spent amongst the dragons, Spike returns to Canterlot to take an entry exam at Princess Celestia's School for Gifted Individuals. His old friend is there to witness it, and she is not too happy with what she sees.

This story is a sequel to The Irony of Applejack

Warning: this story is a sequel. Therefore, it is highly recommended that you read the prequel first before continuing!

Over half a year has passed since the changeling attack on Ponyville, and Applejack would like to think things have finally settled down. Much has changed for the young changeling, and all of Equestria in kind. The new district in Ponyville proves that, along with the town's many new residents.
But there is much the young queen does not yet know about being a changeling. Some things, she will learn, can be chosen, while others will be chosen for her. With new allies and enemies emerging all around her, Applejack must discover what it truly means to rule before the choice is taken from her forever, and the history of the changelings repeats itself, once again...

Image provided by Heilos.

The Princesses find an alien creature barely clinging to life at the scene of a terrifying crash. Can the Combined Power of the Elements of Harmony save it, or more importantly, should they save it? Will the arrival of this strange creature tear Equestria apart?

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https://tvtropes.org/pmwiki/pmwiki.php/FanFic/Article2

There is a flood on the horizon. Equestria's enemies have united, and the coming tide will not only change the course of history on one world, but two, and bring about a monumental meeting that will bring brothers and sisters from those two worlds together.

At long last, the downtrodden will rise.

The battle begins.

Three hundred years after the fall of Princess Luna, Equestria teeters on the brink of disaster. Bitter political infighting and power-hungry nobles threaten to tear the country apart in a bloody civil war, while in the south old enemies prepare to reclaim their ancient homeland from the ponies.

As Princess Celestia desperately strives to hold together her splintered nation, she sends a young pony on a quest to the northern lands that border Equestria in order to plead for aid against the threat of Grypha. This unlikely messenger is Rye Strudel, the flightless, magicless, half-breed son of a guard and a baker. Rye must do the impossible and unite the thanes of the north... for if he cannot, there may be no home to come back to.

Rarity's exploits in "Sweet and Elite" set in motion a chain of events that will find the unicorn dressmaker taking part in the greatest airship race in the world, the Alicorn's Cup. Excitement will give way to terror, as Rarity soon finds herself the victim of a plot against Equestria, and shipwrecked far from home with her least favorite stallion, the boorish Prince Blueblood. Rarity will learn of treachery in Canterlot and abroad, and will have search for something of substance beneath the prince's obnoxious veneer as she struggles to not only save herself, but her entire nation.

Part One of Three
The Adamant Triskelion - Book One: The Flight of the Alicorn
The Adamant Triskelion - Book Two: The Abyssal Forge
The Adamant Triskelion - Book Three: ???