“Hello, Tirek.”

Deep in the bowels of Tartarus, the frail centaur stirred. “Celestia?” he croaked.

At her name, the princess strode into the light. “It has been a long time.”

“Near five centuries, if I’ve kept count,” he said. “Of course, it’s hard to keep count when you’ve only your own thoughts for company.”

“Self-pity does not become you.”

He narrowed his eyes. “Why have you come here? Not to trade pleasantries, certainly.”

She paused.  Then: “Do you know the etymology of the word ‘Tartarus?’”

“What game are you playing at?”

“It comes from Old Earth Pony,” she continued, as if he hadn’t spoken. “They called this place [i]Taru-tírléas[/i]. Literally, ‘the rending of the inglorious.’” She shook her head. “A bit dramatic, if you ask me, but an apt description.”

Tirek scoffed. “There’s not been much rending either time you’ve confined me down here. Just sitting about, waiting…” he twisted his lips into a sneer, “plotting.”

“So far, yes.” Celestia stared at him. “Tell me. Do you feel weaker than you did a few centuries ago? More lethargic? Less… [i]present?[/i]”

Something about the way she stressed the last word put him on edge. “How do you mean?” he demanded. “What do you know?”

She smiled sadly. “This is an ancient place. Long before you came to this land, and long before I ruled, there was [i]Taru-tírléas[/i]: the realm to which the wicked were banished to wait… and to extinguish.”

Tirek’s sneer returned. “I hope you’re not waiting for me to perish. Surely, after all these centuries, you’ve realized that you’ll not be rid of me so easily?”

“Oh, I know you’re immortal. But there is power in this realm deeper than life and death. Tartarus is a place of [i]existence[/i] and [i]non-existence[/i].”

She shifted her gaze, staring off into the darkness which surrounded them. “Those bound in Tartarus exist only so long as the mortal races of Equestria remember them. And when their lives have been forgotten, they disappear.” Her eyes glinted. “Not death. Simply… nothing.”

Tirek’s heart paused. Carefully, he asked, “Am I still well-remembered in Equestria?”

“You are not.”

He looked at his hands. Were they frailer than they had been? He tried to remember what he felt like, a century ago. Had he always been so… insubstantial? “How much longer?”

“Until you are forgotten? That’s a very good question. There are none among the mortals who personally remember you anymore, of course. You are not immortalized in any famous songs or legends. You are not the villain of any holiday, nor the boogeymare invoked in any household. Truthfully, I’m a little surprised you’re still here at all.” She shook her head. “If nothing changes, you’ll disappear [i]very[/i] soon.”

As she spoke, his heart began to race faster and faster, until he could barely hear her over its pounding. “You cannot do this to me!” Tirek cried. “You cannot let me vanish! You wouldn’t! You can’t!”

“I can.” She paused. “But I won’t. Not yet.” She levitated something out from behind her: a book. “To celebrate her 500th birthday, Princess Twilight is about to publish an autobiography recounting her early adventures, and it has a whole chapter dedicated to you.” She sent it through the invisible wards, setting it at Tirek’s hooves. “Given how popular she is, and how grand an affair a quincentenary is, I’m sure that will buy you at least another generation. I thought you might appreciate an advance copy.”

Tirek stared at the book. “Why are you showing me this? What is your plan?”

The sad smile returned. “I believe in second chances, Tirek. And third chances, and fourth chances, and as many chances as it takes. I want nothing more than for you to walk among ponykind freely—as a friend, or at least not as an enemy. I have waited thousands of years for you to take the hoof that is offered, as Discord and so many others have done. Will you not give friendship a chance?”

Finally, he tore his eyes away from the book. “I came here twice in chains,” he said. “I’ll not leave in them, whether they’re physical or not.” 

Celestia seemed to shrink. “As you would have it, then. If you… I hope you’ll change your mind. Remember, though: time is not on your side.” She turned and trotted away, and within moments had vanished into the darkness. “Goodbye.”

For a long time, Tirek didn’t move. Finally, picked up the book.

He hurled it out into the abyss.