Return from the Underground

by Firestorm808

Rating: everyone
Tags: Main 6, Slice of Life, My Little Pony: Friendship is Magic, Princess Luna, Princess Cadance, King Sombra, Adventure, Undertale, Princess Celestia, Crossover
Length: 1213

When the mad tyrant attempts to siege the crystal city, one pony held him at bay. The only distinguishing features of this stallion were his blue hoodie and his large smile.

The Crystal Empire has made its mysterious return back to the land of Equestria. While the crystal ponies attempt to recover from their long slumber, something more sinister also came back. When the mad tyrant attempted to siege the city, one pony held him at bay. The only distinguishing features of this stallion were his blue hoodie and his large smile.

Published 2018-12-11 06:20:02 UTC
Last updated 2018-12-11 06:20:02 UTC

This Is Where It Stops

It has been a long time since the crystal city made its return from banishment. One thousand years ago, King Sombra, a unicorn whose heart was black as night, took over the Crystal Empire. He was ultimately overthrown and banished to the ice of the arctic north. But not before he was able to put a curse upon the Empire. A curse that caused it to vanish into thin air. If the Empire is filled with hope and love, those things are reflected across all of Equestria. If hatred and fear take hold... the world may never be the same.

In an attempt to restore the people to their former glory, Princess Celestia tasks the Elements of Harmony to assist Princess Cadence and Shining Armor in protecting the crystal ponies. However, the Empire isn't the only thing that's returned. Something keeps trying to get in.

The Mane 6 try to set up the Crystal Faire to reignite the will of the people, but they were not able to find the crystal heart. The whole purpose of the Crystal Faire is to lift the spirits of the Crystal Ponies. The light within them can power the Crystal Heart so that the Empire can be protected. King Sombra had hidden it away where nopony would ever see it again!

From over the horizon, a dark shadow presses against the pink shield with more force. Red irises in bathe in a green and purple aura, staring at the citizens in utter contempt. Each second, the barrier gets weaker and weaker. Slowly, Sombra's influence bleeds through.

With all of the chaos going on, no one noticed a figure digging from beneath the fields in the outskirts of the city. When it finally emerged to the surface, it analyzed the oncoming threat. "Over lv14. Hmmm."

Crystal Empire - Present

Large pieces of black crystal are strewn throughout the streets. The sky flickers between a pleasant blue and an ominous orange before Cadence finally loses all of her strength to keep the evil at bay. The shield surrounding the city dissolves away.

Pinkie felt a large chill move through her tail. "That one was a doozie. Something big is about to happen guys!"

Sapphire Joy cried in terror. "He's back! I can't take it!" She attempts to run away only to be stopped by another clack crystal. "Ugh!" Looking up, she sees the smokey figure of their former King

Rainbow Dash paled a bit. "Yeah, and I think we found it."

King Sombra looks down at her in maliciousness. "Ahhhhhh..."

Sapphire Joy shrank to the ground. "King Sombra...!"

The non-corporeal Unicorn rose in the air. "My crystal subjects... It's been too long." Before Sombra could descend upon the masses, a lone figure stood in his way. Sombra's eyes narrowed intensely at the being. He was someone Sombra was all too familiar with.

Only a few ponies in the crowd recognized the interloper as well. Strangers at a distance would say they saw a white pony, but they were mistaken. He was a being of pale bones. His white pupils in the black void of his eyes looked at the imposing tyrant. A dimpled smile beamed from his skull. He wore an unzipped blue hoodie, a white t-shirt/sweater, and a pair of slippers. The pony skeleton looked up at the king unimpressed. "Huh." He remarked, holding a hoof up to his forehead before squinting a bit. "It's been a long time since I last saw the sun..."

Fluttershy hid behind crystal, fearful of the mad king.

Rainbow Dash was confused by the new stranger's appearance. "Who's that?"

Applejack shook her head. "I don't know, Rainbow, but it seems like he's our only hope of stalling till Twilight and Spike make it back with the heart."

Rarity was glad for the help. "Assistance aside, I must say that the jacket looks incredibly drab."

AJ and RD looked at her dryly. "Really?"

The King spoke the name with poison. "Sans..." Immediately, the crowd of ponies looked at the jacketed pony in realization.

Sans kept up his smile. "Heya, Sombra. You've been busy, huh?"

"You again..."

"Yup. I gotta say, judgment-wise, you're still a pretty bad pony after all these years. You wandered hurting anyone who goes against you." The smile shifted to a frown. "You've even taken away those close to me without seemingly any remorse. I couldn't stop you before the princesses arrived, and they knew that too. They couldn't kill you, but they could seal you. You dragged the empire along for the ride as well."

Sombra snorted at the attempt of guilt.

"We're free now, and you're up to your old tricks again. That's just plain messed up." Sans shrugged. "I guess it's my turn to deal with you."

Sombra frowned at him. "It seems like there is one more thing to take care of before I reclaim my empire. You will be nothing, just like all those who came before. You were always called the weakest."

"Really now?" Sans paused before starting again. "Before we do, I've got a question for ya. Do you think even the worst pony can change? That everyone can be good if they just try?"

Sombra simply glared at Sans with utter contempt. Slowly, the smoke condensed and revealed the new physical body of the King. The bloodlust permeated the air, and his answer was clear.

"Heh heh heh heh... All right. Well, here's a better question." The nearby elements realized the skeleton's tone had shifted. It was now lower...darker. Colder. Crueler. "Do you wanna have a bad time? Cause if you take another step forward... You are REALLY not going to like what happens next." The crystal ponies started taking cover, and the Elements did the same.

King Sombra took an aggressive step without any hesitation. "This is a long time coming, old friend, but I will fulfill my destiny."

"Destiny? Please... Like you actually believe in that. I know exactly why you started this path." Sans sighed at his final choice. "Welp. Sorry, Princess Amore," he muttered. "This is why I never make promises."

Sans tapped his hooves against the floor. Suddenly, the world went dark, as if the light of the universe itself had been put out. The world looked like a living black and white photograph. One color stood out, and the ponies saw an unmistakable red heart in the King's chest.

High above, the royal couple looked down, confused yet relieved by the situation. "What's going on?" asked Cadence.

Shining Armor shook his head. "I don't know, honey. All I know is that Twilight better find the Crystal Heart quick."

Within the Castle's catacombs, the student and her apprentice had no idea what was occurring on the surface.

Sans gazed at the pastures around them as black crystal slowly grew closer. He stood straight before speaking again to Sombra, eye sockets closed. It's a beautiful day outside. Birds are singing, flowers are blooming... On days like these, ponies like you... Should be burning in hell. Suddenly, San's left eye flashed blue and yellow frantically, and he raised his left hoof.

Author's Note

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