The Royal Herd Begins with a Nightmare

Alex groaned as he returned to consciousness, the last conscious memory was an Alicorn made of lightning leaping at him then the sensation of his body being reshaped and headaches as knowledge was crammed into his skull before he blacked out.

As conscious thought returned to him he noticed a few things. First, his body was no longer human. Second, he had wings. Thirdly, he had a horn making him an alicorn. Moving the arm ended up underneath him, he checked his crotch and found he was still a male. Once he had that last piece of information he stood up and caped his wings.

"Mmmm." Came an appreciative hum.

"Who are you?" He asked after spun around and got in a defensive stance.

"Nightmare Moon." She replied.

The name caused Alex to drop his stance as the see through mare was more powerful than him. It also caused him to say without thinking, "Then I am in Equestria."

"Give the stallion a prize."

"How did you become all see throughy?"

"Side effect of being blasted out of a pony by the elements of harmony."

The Alex thought a moment. "Makes sense." He allowed. Seline swallowed then said, "If you can give a body, I'll be your first mate."

"!!!!!" The shocked look on his face caused Seline to smile as she said, "Equestria is in trouble. The Caribou have invaded from the north. They've annexed the crystal Empire corrupted the crystal heart enabling them to turn the majority of the stallions to their way of thinking."
She sighed. "As long as I remain nothing more than a spirit, I can't help my ponies."

Upon hearing of the caribou's conquest of Equestria Alex became furious. "I'll help you." He said to her. "I'll free Equestria from the carabou's grip, undo their control over the stallions, and restore anything they corrupted." He then smiled at her and adding with added, "As well as giving you a body. So I'm going to seal this vow with a kiss."
His magic surged as he kissed her on the lips creating a body for Nightmare Moon. She was tall with wide child bearing hips and H-cup breasts. Her body was mostly hard muscle without looking like a body builder, her was long and pointy. Finally her wings were full with magnificent plumage.

Their kiss got more and more intense as both alicorns explored each other's bodies.

On a balcony in Canterlot, Dain Stonehoof was forcing Celestia to her knees when a pulse of magical energy washed over the land. The Caribou King suddenly felt that he had a rival out there.

In Ponyville, the energy wave washed over the earth pony village and the stallions, mares and Caribou witness the spell that bent the stallions to the caribou's way of thinking become visible then shatter like crystal, releasing them. And restoring the mind of the mares.

Somewhere in the Everfree, the energy wave washed over an encampment of the resistance. Luna stepped out of the command tent and looked in the direction of the Castle of the Two Sisters. She frowned at the feel of part of that wave.

Fluttershy and Xecora walked up behind her with looks of puzzlement. "An event from the Castle of the Sisters Two bodes well, but for who?" The Zebra rymes. Luna nods as she remembers again how surprised that Celestia had had a secret passage that lead to their old castle in her quarters.

1In an abandoned cave in the frozen wastes of the south an ancient mind awoke as the wave passed over it. "The king is home." It said, "It's time for a harem once more."

As Celestia's sun rose above the horizon, it cast it's warming rays onto the castle as a group of stags approached the castle having made their way following the path that six mares once took from Ponyville. "It galls me that we had to use that path to reach here." One of the bucks grumbled. "I mean this place is nothing but a pile of rocks that the King's slut used to live here." Another popped up saying, "There are rumors that a resistance cell led by the sister of the King's Slut. That cell is rumored to be hiding in this forest. The garrison commander says the unit that captures them can have their pick of the sluts." This got the caribou to laugh mercilessly.
The leader let his bucks laugh before he called a halt. Once they came to a halt he said, "Alright listen up. About the middle of the night an thaumic energy wave washed over Equestria. What effect it has had not been revealed save the stallions have become unruly and the mares are being more resistant to being put in their proper place. Add to that stallions with the military have gone AWOL. We have been sent here to search this place thoroughly. Any outlawed books are to be burned and any ponies detained as traitors. Any questions?" None of the fifteen others had any.
They split into four groups of four and entered the castle unaware that they the first payment of the price of Equestria's freedom from Dain.

Alex groaned as he awoke. He went over the events of the previous day. He gotten up and went to school and took his finals. He had a minor adventure helping an old lady when her purse was snatched by sticking his arm out and clothesline him because he jerk looked behind himself and to taunt her. It was when his mind reached the point where he gave Seline a new body and took her as his own he sat up straight, had a wingboner so hard that he nearly dislocated his wings.

Quickly, looking around he saw his alpha mare curled up to him, with her Mane light blue and looking like Sunny Starscout's at the beginning of the fourth My Little Pony movie. He chuckled then looked at his horn. "Geuss I'm an alicorn stallion." He muttered. "With the ratio of mares to stallions being four mares to every stallion it was only a matter of time before a alicorn stallion would makeg an appearance." He got out of bed, being careful not to wake Seline, he walked out of the night princess quarters. He thought about Seline's body created by his magic. She was slender and very toned, her breasts were large and sensitive. Being a biomancer has it's perks even if the knowledge of it had been crammed into his brain. Thank havens he was unconscious through the trip here.

The sound of wings followed by a soft clop of hooves prompted him to turn around with smile on his face thinking it was Seline. Only to find himself face to face with none other than a Luna

Author's Note

The Royal Herd currently stands as
Nightmare Moon
Luna
Celestia
Twilight Sparkle

Should I include candance?