The backdoor to Tartarus
I'm not entirely sure where Tartarus came from or how it's connected to the doors, but one thing is for sure. It was built by someone, and whoever constructed it left a backdoor just in case they ever needed to get out.
But the backdoor was even more difficult to get to than the front door. Deep within the caves of the mountain, a small round door inscribed with runes and a faceted depression that looks like a gem might fit sits unassumingly.
Even if the door is moved or dug around it does not lead to Tartarus. Only when the door is opened does it connect the red cave system. The stone changes suddenly from a gray shale to a red granite.
Whatever magic was used to create the doors predates unicorn magic. But a relic just as old was able to unlock the door. A gem-encrusted golden skeleton key that I've used many times does seem to open the door, but only barely, and then it needs some time before it can be used again.
But even though the door opens, it took many moons of mapping before I found the main chamber. Tartarus was a mishmoshed cave with offshoots and turnarounds at every corner. After moons of mapping, I finally found the main cavern, and just as the stories told, a large three-headed dog slept with several creatures chained to the floor around him.
This was the first time I had seen the front door from the inside. Interestingly enough, there was no keyhole on the inside. It seems that if one had enough magic, the door should be able to be open the door from the inside. The creatures themselves had little magic, but I suspect combined they might be able to open the door.
As Cerberus slept, I talked to many of the inmates. Most were just large monsters, but a few were intelligent. One such character was one who called himself Tirek, or Lord Tirek if he is to be believed.
He and I spoke many times. He often tried to convince me to let him out, but I refused, since I knew I would need him later. But in time I did make a deal with him. He knew of Tartarus long before it was called such. He spoke of a magic school that taught only the most advanced magic.
Years before it was converted into a jail, it was a thriving school that taught all type of conjurations, elemental control and numbers subfields of obscure magic. They even taught dark arts deep within the caves. Hence the reason the school was cut off from the outside world.
Tirek said deep within the labyrinth there were classrooms and libraries and all sorts of interesting magical items. He spoke of a master that went to the school and taught life magic. Perhaps one day I would travel to Tirek lands and learn from his master as well. But now my attention was turned to the cave and finding the school.
I struck a deal. If I found the school and found it useful, I would release Tirek and provide him just enough magic to open the front door, on the condition that he forget about me and never speak of me again.
I moved deeper into the cave; soon the rough stone became too smooth and eventually looked carved. Before me lay a large set of metal doors which luckily were not sealed by magic. Behind them lay a cavernous main hall to the school.
Vast hallways and rooms, all for practicing and experimenting. Rooms filled with strange markings and materials of all shapes and sizes. But this place was huge, and there was no way a single pony could view all of it.
But with an interesting mix of magic, two spells called Accelero and Simerlo Duplexes. I could literally be in two places at once. But I was not limited to just two clones. I made an army and had them search for libraries and notebooks. Their orders were simple: to absorb all info related to magic at the school, especially the dark magic that seemed to have been lost to the ages.
Each clone was somewhat limited and could only handle so much information. The nice thing about the clone was, when it returned to the original, all the memories, emotions and things it had done accumulated in the original. Over the next several days as I explored the ruins, clone after clone returned.
It was not long before I had accumulated generations of learning and magic from those that predated much of the magic the ponies had made. I would come back to visit and experiment, as Tartarus provided a rather useful place where no one would notice, since few ever visited.
When I returned to the main chamber and caught Tirek’s eye, he proclaimed loudly that he thought I had died in the tunnels. I silenced him quickly; Cerberus only shifted in his sleep and then rolled over into a deeper slumber.
As promised, I would release him with the caveat that he forget me. But I asked him for one additional condition: to wait once he had gotten out. I told him to hide in the forest for a few moons and accumulate magic slowly. Only when he was able to take ponies’ magic at will would he be strong enough to take over; I could not let him fail right out of the gate.
Luckily, he agreed to stay in the shadows for some time, and our deal was struck. With a flash of light and a speedy getaway, he was out of his chains and through the large door. Unfortunately, it roused Cerberus who managed to squeeze between the doors before they closed. I'm sure a few would notice their guard dog missing.
Cerberus being such a large animal it was not long before someone noticed him wondering about. It would be several days before Cerberus wondered into any towns and days before he would be returned, but just in case I did have a plan.
Before heading back down to the school, I left a clone disguised as Tirek for a few days, just in case someone came looking. I spent the next several moons exploring the school and all the things it had to offer before making my way to the main cavern and then to the back door.
On my way home, I wondered what had happened to Tirek? Had he begun his conquest? Was he stopped? Did he further my plans, or would I have to correct something?
It was not long after I left that I got to watch the show unfold from high above. It was slow going at first but picked up speed as time went on. It was not more than three days before Tirek and his Draconequus friend had guzzled up half of Equestria’s magic.
But as always, Equestria prevailed, and yet another chapter was written in the book.