I guess this is 'Chapter One: The Introduction'
“Tell me,” said the fiend, “why do you still stand? Your companions are all dead- or dying, I have a hard time telling whether you ponies are entirely dead- and your so-called “physical goddess”, the Moon Princess, has been...” It chuckled and delivered an excruciating pun: “taken for granite.” The ever-shifting mass of tentacles, slime, and Celestia-knows-what-else seemed to be enjoying itself, in a way that was really pissing me off.
It was powerful- excruciatingly so. It had managed to knock everypony else unconscious with an attack so fast I didn't even see it. Luna had arrived on the moon before us, and it seemed she had been turned to stone. The world had slipped down and past the horizon behind me, and I felt something I hadn't felt yet- fear, horrible, gut-wrenching fear. Fear of the cosmic horror that loomed before me, changing size and shape seemingly at random. Fear that my friends were going to die. Fear that I would die without ever learning my name. Fear that I would never tell my special somepony that I loved her.... and a crushing truth- nopony, with the obvious exception of those who came, knew we had come here.
We wouldn't be getting help. If I failed, then this piss-poor excuse for a god would bring wanton havoc and destruction to Equestria- and the rest of the world.
“I remain standing,” I said coldly, my voice dripping with the bitter venom of my rage, “because it will probably be easier to kill you from a standing position- it is rather awkward, casting spells whilst sitting down, you see.” I didn't shout, scream, or otherwise raise my voice. If anything, my voice had dropped to a whisper, because, despite the intense emotion welling up inside of me, I was calm- after all, it's hard to do a good job when your tranquility is broken. “Besides,” I said, forcing myself to calm down once more, “your little 'attack' managed to make my flank quite sore, and I would prefer to avoid agitating it further.”
“You are fated to die here,” it said, “I know it because I have seen it. Why should you waste your final moments in a vain struggle to defeat that which is unable to be defeated- unable to be killed?”
“I've always been defiant, according to Olivia,” I explained calmly, as if we were having a nice chat over some tea that I would avoid drinking (I dislike tea), “and, even if I am fated to die here, I think I'll have a go at wiping you from the face of the moon. If I fail, then... well, I'm sure Celestia will have something to say to you about what you did to Luna, and Discord would probably be appalled that there exists a being that is even uglier than he is. And let's not forget the Elements of Harmony, the dragons, the Griffons, and the ponies of Equestria.”
Something I had said in there managed to really piss it off. It definitely lost its cool. “I AM FEAR INCARNATE! MY VERY PRESENCE CAUSES THE STRONGEST OF MORTALS TO GO INSANE! I CANNOT BE KILLED! I WILL BRING YOU AND YOUR WORLD TO RUIN, AND NOTHING CAN STOP ME! YOUR MOST POWERFUL MAGICS AND WEAPONS WILL NOT EVEN FAZE ME! I AM THE HARBINGER OF YOUR DESTRUCTION, AND YOU. WILL. ALL. DIE!”
“Don't freak out about it,” I said in a faux-affable way, “you may be ugly, but you're not that ugly. I mean, really, have some self-respect there, mister-and-or-missus-thing-that-really-shouldn't-be. I mean, look at me. I've been conversing with you for awhile now, and I'm still just as sane as I was beforehoof.”
“YOU WILL LEARN RESPECT,” it bellowed, “AND THEN YOU WILL DIE!”
I briefly wondered if pissing it off was the best course of action. Then I shrugged, smiled petulantly, and replied, “I think you'll find that you're the one who needs to show some respect. After all, I'm going to be 'the pony who killed a self-proclaimed god' by the end of the day.”
“GRRRRRRROOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOAAAAAAAAAAAAAAAAHHHHHHHHHHHHHHHHHH,” It bellowed, enraged. It slithered/rolled/glorped towards me, shifting in size and shape more rapidly than before- which made it really difficult to tell how far away it was.
'Alright, you've pissed it off,' I thought, 'next step... oh, that's just bucking brilliant. You got so caught up in insulting it that you forgot to have any sort of plan...'
'I suppose we'll make it up as we go along, then?'
'Don't we always?'
'I guess- I just assumed that fighting a “god” deserved a little more thought.'
'Hey- I insulted it, didn't I?'
'Wait a second- maybe we did go a little more insane. I don't think I've conversed with myself before.'
'Let's consider this an advantage.'
'So... Railgun to the face?'
'Railgun to the face has yet to fail us.'
'Railgun to the face is the solution to all problems.'
'I hope we get paid for this.'
'It's not a monster, though... probably. It's more of a... disgusting fiend, maybe?... an aberration? A cosmic horror? Eldritch abomination? Upper-tier mid-boss? Hrm... let's just stick with “ugly”.'
I didn't have time to tell myself 'Oh, hey, look at that gigantic tentacle that's coming right for us'.
0~O~0~O~0~O~0~O~0~O~0~O~0~O~0~O~0~O~0~O~0~O~0~O~0~O~0~O~0~O~0~O~0~O~0~O
“I guess I should tell you how I got here before I go any further, eh? After all, I can't waste a perfectly good cliff-hanger, and I kinda started in the middle of the story.
“I mean, it's pretty obvious that I lived, because... well, I'm here, aren't I? Besides, I am pretty buckin' awesome- it's not like some monster could defeat me. I'm The Railgun, for Luna's sake! That's Railgun with a 'The'- capital 'T' and everything!
“And do you know how I became the pony I am today, fillies and colts of Princess Luna's Academy for Extraordinary Young Ponies™?
“I'll tell you, because, even though I'm sure you hear this every time somepony comes and gives a speech, I can attest that, for me, it is mostly true. I studied (at least, I made sure to at least skim through the books assigned to me), I persevered, worked with a team of amazing ponies, and had a teacher that scared me senseless. I also drank a bit too much coffee, but that's really pretty irrelevant and I should stop talking now.”
I clear my throat- you seem to be listening eagerly, and I'd hate to disappoint such an adorable little foal- and begin to tell my story, from the beginning this time.
“A little over three months ago...”