(A/N: the auxiliary chapter will be posted after a whole because there is A LOT to write as I am copying word for word from the CYOA so you don't have to go back and forth between the story and the pic in the comments, enjoy.)
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At night we can see an average 21 year old on his phone looking at CYOA's, until one catches his eye, after filling out the CYOA(look at auxiliary chapters for what he got) Jack blacks out and is transported to a parallel world as his body and mindset change.
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Opening my eyes, the first thing I see is the inside of a ruined house with a wall completely gone and outside it looks like a post apocalypse scene from a movie.
"where the f@ck am I?"
Getting up off of what looks like a small half melted couch, I stand up, only to hit my head against the roof, making a new hole, crawling outside which felt 'natural' and a lot more easier than before but with the grace of a bull in a China shop 'smashing things with the slightest touch' as the room seems really small; I sit down and look over my 'new' body, I now have concrete coloured skin, if I stand straight I will be a lot taller than before as the door frame only reaches the middle of my thighs, I now have 6 'main' arms kinda like an asura and 4 smaller 'secondary' arms 1 pair are on my chest the other a little below them, which I guess is for handling smaller 'human' sized things, luckily the 'secondary' arms are as strong as the 'main' arms, each arm has a water jet in the wrists that can shoot pretty fast and pierce into the concrete, all arms looks like a normal human arm except for the retractable claws instead of fingernails which are sharp and strong as they easily dig into the concrete below me, I have two legs that are digitigrade or look like a dogs back legs including sharp claws, I have 6 tails that look like a certain half-ghoul kagune but with small retractable spikes at the corners that start at the base (near me) and end just before the tip as the tip is a spike itself, all over my body there are hidden flaps with quills in them, the flaps cannot be seen unless I open them up as they look seamless, I also have flap things like a flying squirrel but are fully retractable so I think I can glide, and now the most important part of my body the head, or heads in my case as apparently I haven't been turning my head to look at everything, instead I have 10 separate heads which gives me 360° vision if I get all heads to look at different directions, I can also stretch my necks to look like a hydra and it must look really creepy if my shadow is any indicator, all heads look like a human head with eyes, mouth and nose but bald and with a crown made of spikes and no ears, each head has a mouth filled with spiky teeth and a prehensile tongue that is about as long as my main arms and is covered with tiny retractable spikes all over it and my eyes are pitch black.Oh and I am acidic or corrosive because while I was sitting there looking over my body the area under me turned a little soft, and when I got up there was a indentation of me, but lucky I can toggle it off and on.
As soon as I am done looking over my body, I get a small headache from a lot of information and instincts flooding my mind, apparently I was correct on all the above but I also have an electric touch, my spikes are lethat as f@ck as they have a powerful and fast acting neurotoxin that paralyses ans slowly stop the heart of a human, aswell as causes extreme pain as it Eats them from the inside, can swim and breath underwater better than a fish, get bigger while immersed/recently immersed in waterr and have a sonar/echolocation in my heads, my touch causes severe chemical burns that can easily eat away at a human with just the slightest touch, I also have the abilities to cast strong illusions, shapeshift into a human or inanimate object that cannot be smaller than a human and gain memories from eating human brains. But this all comes with a couple small drawbacks as now I have a small psychological fear of faith specifically Christianity, but lucky it is not the type where I see a cross and burn in holy light but just recoil form it and that is only if a human that truly believes in Christianity wields it, so I can still y'know shoot them with a quill that explodes inside them or throw pebbles at them which would tear them apart kinda like a shotgun. Anyway apparently I now have an addiction to a blackflower which only grows in the city, luckily it is uncommon but the bad thing about it is the fact that if one is crushed, it releases a scent which is irresistible to me, the reason I say this is bad is I have to go to the location it was crushed and smell it consequences be dammed, also they can be taken away and crushed latter on and still effect me, yeah that screams monster lure to me.
And last but not least music... Yes I know the big scary monster has a weakness to music, but let me explain, the music has to be played/sung by a human at that moment to effect me, so no recordings, no using speakers to boost the sound unless it needs them(electric guitar), and it only calms me down so I don't kill the pest, but as soon as they attack me I'll kill the f@ckers.
Apparently I don't need to eat, drink or sleep but can still do it if I want, I have insane defenses as high caliber bullets only pierce a few inches if hit, the older i am the stronger I get AND if I die I respawn 1 hour later in a safe zone... Op pls don't nerf, anyway apparently unlike the CYOA this city was transported here by a dimensional collapse and a bored outer god, because of that all citizens of the city will be transported with the city when it changes dimensions, there is also a mission board for any citizen that are bored and want to pass time and all citizens have it as a holographic display. And yes there are leader boards for different things like kills, fame, infamy, exploration, deaths, longevity and they can be split up even more like kills of specific things and so on. Also there is a chat group with 5000/5000 citizens with sub categories like a game, but that's not all, all 5000 citizens are like me they are people from my original earth that have filled out the CYOA and were transmigrated into a giant ruined city in a new world as the monster we created. Luckly we have a stat page so we can see our abilities and some other simple stuff,mine looks like this.
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Citizen name:Jack
Username:Jack The Ripper
Sex:Male
Status:alive
Age:10 minutes
Abilities:[spikes Lv2] [electric flesh Lv1] [sonic blast Lv1] [claws Lv1] [corrosive touch Lv1] [jet cutter Lv2] [quills Lv2] [illusionist Lv2] [shapeshifter Lv2]