Hell doesn't involve burning. No matter what the saying says.
I passed through the Underground again and again. First as a wanderer, confused and frightened. Then as a hero, salvation to those who had so long lived in despair. Then as the angel of death, a walking disaster, doom of all.
It was my intention to fix what I'd done, to go back and end things on the best note I could manage. That power, after all, had let me go from wanderer to hero in the first place: the ability to go back in time and revise what I'd done. To correct my mistakes. To perfect my skills. Or simply to see what other futures might be possible. Sometimes the people of one timeline could dimly recall the residue of a past history, as if smudges remained on the blank slate I'd cleared. But eventually I refined my control until even those could be wiped away.
Somehow, though, I caused enough destruction with my march of war that the path of time was itself irreparable. I could not go back: there was nothing to go back to. I foundered, a consciousness and memory adrift in a howling void. I cast about for something to orient myself upon. I cried out the names of those I had befriended and destroyed. But nobody came.
I don't know how long I remained in that state. Perhaps it cannot be counted, given there no longer existed any seconds or hours or decades to compare against. But somehow, eventually, I did hear a voice. The voice of the one I'd met briefly at the end, before everything unraveled. They'd congratulated me on the carnage I'd wrought, staring back at me like a mirror glamored to show only my worst qualities.
I realized, given so little to distract me from it, that it was my voice.
"Do you think you are above consequence?" they asked. I stammered out a "no," though if I'd been honest, of course the answer was "yes." I'd managed to undo everything else. Why not this?
They made me an offer. It was so trite I nearly laughed, but bodiless and panicked as I was, nothing of it conveyed. My soul for the world's restoration. My soul for the restoration of the powers I felt so lost without. My soul for another chance to make things right. That soul had been crucial to my prior adventures, as a key to the freedom of the Underground or a power source for its obliteration. I could hardly imagine making the journey without it. But desperate for an alternative to the nothingness, I accepted the offer.
And there I was! Back at the beginning, just like all those times before. What's more, my soul still hummed in my body, right where it belonged. Had my double made a mistake? Had I managed somehow to renege on the fee for their services rendered? I felt a surge of hope. With renewed determination, I strode forward on what I planned to make my final traversal of the buried world.
I conducted myself like a saint. I raised not a finger in violence against anyone. I spoke not a single harsh word. And at the end, I burst the prison gates. I led everyone forth in triumph to a life of freedom aboveground, for the second and final time. I'd learned my lesson: I would not reverse this timeline for any petty ambition or curiosity.
That night, my adoptive mother tucked me into bed in our new new home. As she turned to leave, a warm smile on her face, I heard myself speak.
"Mother?"
I had not meant to say anything. I tried to knit my brow in confusion, but the reflex remained only in my mind. My muscles no longer obeyed me.
"Yes, my child?" She turned back to me, ready to grant whatever I might ask.
"Can I have a goodnight hug?" I asked, sweet as could be.
Her smile turned positively beatific. "Why, of course!" She returned to my side and bent down, arms outstretched.
I drew a long knife from behind my pillow and buried it to its handle in her throat. I have never, even at the height of my most rampaging timeline, seen such an expression of shock, confusion, and betrayal.
In horror I reached for the power I had so recently sworn never to use again. It obeyed: time snapped backward, and I found myself Underground again, moments away from the exodus, heart pounding. Where had that knife come from? I found it in my little satchel of things next to a heart-shaped locket, both gifts from my parents-to-be at the end of my journey. With a revulsion bordering on nausea, I hurled the knife away into the darkness. I would never touch a weapon again! I proceeded out into the light one more time.
Absent the knife, I simply seized her by the throat and dragged her down to smother her among the pillows.
I rewound again, mind racing. I had worked so hard to purge myself of killing intent! But the truth was obvious. It made no difference what level of violence I cultivated in my own soul, for it was no longer my soul, it was theirs. And they had the combined murderous power of every choice I'd ever made to strike down another creature, rewinds be damned.
So this time I declined the offer of adoption, to go my own way in the world above. I could see the disappointment in Mother's eyes, but it was a small hurt compared to the alternative. I bedded down in a hostel that night, and though the terrors of the last several timelines made it hard to fall asleep, eventually I succumbed.
I awoke in an unfamiliar room with something heavy in my hand. A hammer? It was still dark outside. In a bed nearby a figure lay snoring. A beam of moonlight from the window behind me illuminated the red of a capelet around his shoulders—he'd not even take it off to sleep, apparently. I strode forward, raised my weapon, and brought it down to crush his skull.
No matter what I did, the outcome was some variation of the same. I might find myself beheading the king, or setting fire to the apartment where the leader of the royal guard and the royal scientist lay entwined, or blowing up the comedian in a sick variation on one of his own pranks. Once I left the underground on any given timeline, the owner of my soul did as they pleased, and what pleased them was for me to witness the deaths of my friends by my own hand.
Was leaving the Underground the key, then? Was breaking that barrier what let my doppelganger seize control? I returned to the beginning, to my entry into the Underground, which had always been as far back as I could ever go. It was like stepping out of the void again, though instead of grinning with hope, I now shivered with dread. To my relief—a slight one, but relief nonetheless—my theory seemed to hold. I could act freely within the Underground. At times I felt a vague alien presence, like an intrusive thought or sudden temptation, which in my paranoia I attributed to the other-me. But that was all.
When I saw Mother again (or, from her perspective, for the first time) I broke down. Through my tears I tried to explain what had happened, what I had done, the terrible price I had paid. But it made no sense to her, a blubbering child ranting about deals with devils. She took it as a sign of my distress, perhaps a head injury from my fall, and treated me with the comforts of home that were always her way. Pleasant, but not a cure.
I moved on from the ruins she called home, then, and poured out my story a second time, to the comedian. He was more receptive. His mouth remained set in his customary grin, but his eyes quickly grew hard and serious.
"I warned you, didn't I." I nodded. He had, or rather, that timeline's version of him had. But he knew enough of the many histories' secrets to understand what I was talking about, and knew what he would warn me of, had the chance presented itself. "And you went ahead and did it anyway." I nodded again, eyes downturned. He sighed. "I can't fix this, kid. It's not the kind of thing that can be fixed." He looked aside, to the tall dark trees surrounding the snowy path where we stood. "There's only one thing I can do for ya, and it ain't nice."
His meaning was apparent. I'd seen what he could do, though in most timelines he kept it very well hidden. And though it chilled my spine to consider it, I realized it was the right choice. My alter ego's soul still resided in this body, and if we destroyed it now, they could no longer use it to their horrific ends. I wrapped my arms around myself and closed my eyes, but steeled myself enough to say yes. Do it.
Seconds passed. Then the comedian sighed again. "Sorry, kid. Sorry, old lady. Sorry, bro." There was a sound like feedback from a microphone, a blast of blue-white light bright enough to filter through my closed eyelids, and a rush of excruciating pain as my body disintegrated.
It was not the first time. In other histories, my desperate determination to live triggered an instinctive use of my powers, rewinding away from the moment of my demise. I did my best to let go of that desire, to accept my fate as just reward for my actions. To let myself die.
But again: when and how to dispose of this soul was no longer mine to decide. The rewind happened whether I wanted it to or not, and I found myself back in front of Mother's house.
I tried so many things. So many bizarre, desperate things. I threw myself into chasms filled with lava. I had the royal scientist put me on the operating table to drain the soul-stuff from my body. I sequestered myself in the first cavern of the Underground until I died of thirst. I went on television broadcast to the whole of the Underground and proclaimed that I am not to be trusted, that I am a thing of Hell to be shunned and spat upon. But it changed nothing. The parameters of my torment remained the same. If the Underground went free, I became a killer; if anything threatened the integrity of my soul, I fell back in time.
Now I skulk about the ruins, in the city called Home. I let no one see me if I can help it; it is better if those I once called friends never get to know me. I steal and scavenge to stay alive. When I can, I do little secret kindnesses to make the locals' lives better: repairing broken things and returning lost ones, for example, like a benevolent fairy. It's my fault they will never see the light of the sun, after all. I can give back a little effort for all that I have taken. Someday, I'll die of old age or disease or accident, and the whole enterprise will start over.
I wanted to witness every ending. Now there will never be one.