Lord Tirek sat in his prison of steel and stone, staring out across the hellish landscape. "Ah, another lovely day in Tartarus," he whispered to himself. "Yes, a lovely day indeed." He smirked to himself as he watched Cerberus pace far below. "Now, where is that pony..."
He leaned carefully against the bars, taking care not to put too much pressure on the weakened metal; still, he could feel them shift against his weight, the movement drawing a smirk to his face as he glanced down to examine his handiwork; from the outside, the bars looked unharmed, but from the inside...
From the inside, their compromise was obvious. It had taken months – and more than one rock from his unwitting accomplice – but at last, they were weakened to the point where escape was possible. Only one more piece of the puzzle remained.
"Hello!"
Lord Tirek smiled at the greeting; everything was going according to plan. "Hello, friend," he rasped, looking up at the hovering pegasus. "You brought my magazine, I trust?"
"Yup!" She landed beyond the edge of the cage, reaching back into her saddlebags and pulling out the latest issue, wood-paneled walls and opulent furniture sprawling out across the cover.
"Thank you," he said, grasping the magazine gently between his withered fingertips. "Though, a favor, if you would."
The pegasus paused, tilting her head, the wrong eye focusing on him. "Do you need another rock?"
"No, not at all. Indeed, it is nothing for me." Lord Tirek leaned forward earnestly. "Tell me, have you noticed the guardian of this place looking... bored?"
"Uhhhh..."
"Because I assure you, he has, how should I put it... a dearth of entertainment."
The pegasus scratched her hear with her hoof. "Okay."
"I was wondering..." He reached back behind him, gathering up several balls of paper, the red roses bright as ever on the crumpled pages. "Could you gather these for me, and drop them for Cerberus on your way out? I am certain that he would find them an enjoyable diversion."
"Okay!" She gathered the balls up in her hooves against her chest before pausing. "Uhm, doesn't he have to guard you though?"
Lord Tirek put on his most winning smile. "Me? I'm trapped in this cage. There is simply no way for me to escape; he is mostly a formality."
"Oh, alright," she said, slowly fluttering off, dropping a couple of the wadded up balls of paper as she made her way down the mountain.
Lord Tirek smirked as she flew lower, more of the balls falling out of her hooves, one of them striking the guardian on its centermost head as the dumb beast looked confused for a moment, then barked loudly, chasing after the mailmare, who rather quickly shed the rest of the balls and began flying away as fast as she could, the monster close on her hooves.
"Hmph. Who knew the monster was so interested in pegasi? I didn't even need the balls." He shook his head and chuckled, before turning around, leaning forward before slamming his hind legs into the weakened bars, the metal shearing off with a satisfying clang as the bars bent outwards. Turning around, Lord Tirek stepped forth through the gap, squeezing through the opening he had made, his hoofs thudding quietly against the smooth stone. Striding out to the edge of the mountain, he looked downwards; there was no sign of Cerberus.
He threw back his head and laughed. He was free.
Ditzy you silly filly, didn't your mother ever teach you not to talk to strangers ? They have a way of escaping from their monster-guarded prisons in the pits of Tartarus and exacting revenge on your entire race if you so much as look at them!
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Apparently not! Shame on her for missing such an important moral lesson. I can't imagine how she missed out on giving it to her daughter.
4483176 But... if you don't ever talk to strangers, then where will your new friends come from? (Got to look at this from the Equestrian perspective, you see.)
That said, where was Tirek for the two years/year and a half between "It's About Time" and "Twilight's Kingdom", if he escaped this early?
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It's true! Friendship is magic there! Literally! Gotta meet those strangers to get more buddies.
As for the other: presumably he was hiding in an alley somewhere.
It isn't really clear from the show how much time has passed between It's About Time and Twilight's Kingdom; it is hard to say, and there's no real clues, like a winter episode or anything. Could be anywhere between several months and a couple years; all we really know for certain is that at least one year has passed since the premier, as Princess Twilight Sparkle has the Summer Sun Celebration, an annual celebration, return, but it seems to imply that it is the first one since Luna's return:
Though that is kind of vague and can be seen as a general statement about the celebration in general being different to her after a thousand years of it sucking.
We also saw our second Applebucking season in Bats, which is further (fairly weak) evidence that we're in year two of the show, chronologically, which would require that Fall Weather Friends, Winter Wrap-Up, and Hearth's Warming Eve all were not necessarily broadcast in chronological order, representing a single fall and winter. Though we actually already know from Secret of My Excess that Fall Weather Friends and Winter Wrap-Up weren't in chronological order relative to each other, because that episode covers Spike's first birthday in Ponyville.
That being said, Twilight's Kingdom has Luna express her belief that this was how it happened, so wherever he was hiding, he was probably doing it for quite some time:
Yes, I may spend a little more time thinking about this stuff than is really necessary.
I hope you enjoyed the story, though!
Tirek finally escapes. It’s about time.
...Wow.
Methinks they need to tighten the security on this prison a little.
Dammit, Derpy! It's all your fault!
"I didn't even need the balls."
--Tirek, probably
Ah, and now we see how this fits in with canon timelines.