This is my first fan-fic so don't expect this to be the most amazing story ever. Disclaimer: I do not own Adventure Time, sadly, only my OC's and this story.

Chapter 1: A New Life

(Normal POV)

In another dimension, known as the Nightosphere, a dark figure enters an enormous colosseum. The figure walks out of the shadows, revealing a human boy, cladded in black colored light armor. He has a black helmet on, covering his black hair, but people can still see the scars on his left eyebrow and his right cheek. He was wielding a sword made out of demon's blood, giving the blade a crimson red color, with a golden encrusted and enchanted handle with black runes on it. The human looks up to the thousands and thousands of spectating demons in the stands, cheering and shouting, waiting for the carnage to begin. The human, who looked about an age of 18, looks across the field to see three demons ready to fight.

The demon on the left was red-skinned, like most demons in this realm, with bat wings on his back and pointy ears while he wields two swords. The demon on the right had brighter red skin with a head of an ant. He was holding up a spear in his hands while wearing grey light armor. In the center of the three is a more taller, stronger, and yet more grotesque demon. He wore heavy red cladded armor wielding a battle-axe.

A bloodmist cloud floated over the arena and spoke in a booming demonic voice.

"YOU ALL KNOW THE RULES. NO MAGIC IS ALLOWED BUT ANY DIRTY TRICKS CAN BE USED. IF YOU ARE BRAVE ENOUGH AND WIN, YOU WILL GAIN YOUR FREEDOM. BUT IF YOU LOSE,"

The bloodmist cloud evaporated to show a demon with a bulbous green head, horns on the top, and black tentacles on it's back. It wore a black business suit, a red tie, and red boots.

"YOU WILL BE KILLED BY MY APPRENTICE AND CHAMPION OF THE NIGHTOSPHERE, BLOODLUST!"

He points down to the human boy. Bloodlust gives a look over to the other demons that says "I'll kill you all so easily". The trio is unturned by Bloodlust's death stare, with bravery in their eyes, still holding their confident postures.

"UNDERSTOOD?!"

"Yes Hunson Abadeer!" The demon trio yelled to the vampiric being levitating above them. Bloodlust simply gave a nod to his master.

"THEN LET THE BLOODBATH BEGIN!"

Immediately the crowd of thousands scream in excitement while the three challengers wait for the human's first move. What seemed like an eternity, the ant headed demon finally makes the first move by lunging towards the boy. Bloodlust did not move until the last second. He took a few steps to the right, avoiding the spear. With one swift motion of his right arm, Bloodlust decapitates the demon's head like cutting butter. The bat-like demon gets nervous at the sight of this but keeps his confidence up. The grotesque demon is unphased by enemy and just smirks at the human.

"Hehe. Is that all you got?" The taller demon snides at the boy.

"Oh I'm just getting started peasant." Bloodlust retorts to his opponent.

The axe wielding demon takes a few steps forward, jumps into the air, bringing his axe behind his head in order to slice Bloodlust in half. With lightning speed, Bloodlust runs beneath him and moves toward the bat-like demon. Luckily for the dual sword wielder, he blocks three of Bloodlust's attacks. But the human counteracts by jumping over the bat-like demon while slashing at him.

"Aaaaaaaaahh!" Was all the demon can say from the horrible strikes.

Bloodlust lands on his feet and drives his sword into the demon's heart from behind. The only thing the demon could do was gasp, breathing his last breathe. Bloodlust turns his sword clockwise, immediately ending the bat-like demon's life, then taking it out.

"Two down," Bloodlust said while he licks his blade, tasting fresh blood. "One weakling to go". The human gives his last foe a small grin.

"Glob your sick man. But I like that in an opponent." The large demon said, grinning back at the human boy.

The two stared off at each other in a stabled defensive stance. Both fighters then charged at each other, their weapons ready to kill the other. As they ran closer and closer towards each other, they finally made contact, slashing at their opponents with one strike. The large demon slices Bloodlust at his left arm, the one not wielding the sword. Blood is running down his arm and dripping onto the ground. The crowd gasps at this sudden change of power dominance.

"..." Bloodlust doesn't say anything from the open wound, his expression blank.

"Haha! Today's the day you finally die! And you didn't even hit me." The demon said, looking very satisfied at what he did to the human, smiling widely.

"Oh really? You better check again." Bloodlust speaks while he grins confidently, not facing the demon.

With a flick of his wrist, turning it clockwise, the demon's armor and chest split open horizontally. His blood gushing out of his chest, screaming at the top of his lungs from the agonizing pain.

"AAAAAAAAAAAAAAAAAHH! HOW?!" The demon couldn't believe what had just happened. He had thick armor on, so how did his foe cut straight through it?

Bloodlust walks up to the fallen demon, who is on his knees, and smiles evilly. He still held his sword in his right hand, holding it up to the demon's neck, ignoring the gaping wound on his left arm. The demon's eyes were filled with terror and blood so he can see everything in red, panting violently as he loses more blood, saying his last dying words.

"This is impossible! No mere mortal human can do the things that you can do. How are you this strong?!"

"It helps when you have been trained by the Lord of Evil extensively as a child like I was. Now, I hope you made your prayers because YOU will die. But remember these words. I... show... no... mercy."

After that, Bloodlust slit his throat with is sword and began hacking at the dead demon's neck. With only two swings of his sword, Bloodlust holds the head in his left hand while holding his demon blooded sword in his right. Everyone watched the human, waiting for the next thing he will do. Bloodlust holds up his sword and the head triumphantly. The crowd of over a thousand demons cheer and scream of excitement, filled with joy of today's entertainment.

"BLOODLUST! BLOODLUST! BLOODLUST! BLOODLUST!" The demon's in the colosseum shout the human's name high up into the skies of the Nightosphere, pumping their fists into the air.

The vampire-like demon, Hunson Abadeer, is impressed yet again by his apprentice.

"THE WINNER AND STILL CHAMPION, BLOODLUST!"

By then, the human takes his leave, exiting the colosseum and heading to his quarters.

As he was walking down the hall, he saw a man wearing a black business suit, red tie, and red boots. He had green skin, with slick black hair, red eyes, and his fangs protruded out from his mouth. No doubt this was the Lord of Evil, Hunson Abadeer, in his normal form.

"Excellent duel today Bloodlust. I expected no less from my apprentice." Hunson said appraising the human warrior, while smiling at him.

"Thank you Master Abadeer," Bloodlust took a bow before speaking . "I don't plan to lose at all during these petty fights. If I am needed, I will resign to my room as always.

"Of course. Carry on and prepare for next week's match," The immortal demon spoke still smiling at the fact that his apprentice is getting stronger and stronger, soon ready to become the new ruler of the Nightosphere. "I expect to see even more bloodshed my heir."

"Yes Master Abadeer." The human took another bow to the Lord of Evil before they both departed.

As soon as Hunson was out of his view, "Freakin' bastard," He thought. "I don't know how much longer I could've stood the stench of him. Even though he raised and trained me, he can still be such a pain at times," The human then frowned at his next thought. "especially to the fact that he may be the one who killed my parents. But I can't let the past get in the way, for now. I still get curious at times but..." Bloodlust shook his head, trying not to get into his thinking moments again. "No I can't focus on the past now. Only focus on the present." He shook his head one final time and continued down the hall to his room.

(Bloodlust's POV)

When I get to the door I open it, walk into my room, and turn on the light to see my somewhat messy room. It's only messy from the small pile of body parts that I keep as trophies. Now my room is simple with only the essentials. A bathroom, a bed, a dresser, and a desk that have some books on it from the Abadeer Family Library.

"Man I have got to start stuffing those body parts so they won't rot in here."

I threw the demon's head on the top of the pile but rolls down off of it and hits the side of my desk. I take off my light armor and my helmet, then my shirt, and examined the wound on my left arm.

"Eh not so bad. I still need to bandage it up." I said while looking through my desk drawers and found a first-aid kit. I opened it up and took out a roll of bandages, a cotton ball, and disinfecting spray. Hunson wants me to keep training and stay strong, so that also includes not getting any diseases which so rarely happens now-a-days. I wipe up the blood with the cotton ball, spray the disinfecting spray on my cut, and wrap around the wound with the roll of bandages. After that, I go to my dresser and change my clothes into my usual look. A white t-shirt with red and black color streaks on it, a dark red button-up shirt, black cargo pants, and my black and white shoes.

I sit on my bed and start to relax after taking a book off of my desk. The book was called 'The Great Mushroom War'. I chuckled a little upon reading the title.

"Hehe even though I started reading this book a month ago, the title still makes me laugh," I look up to the ceiling and smile slightly. I mean, it's the war that caused the extinction of the human race, so why was it called 'The Great MUSHROOM War. But I've only gotten that far into what this book is about. I'll find out soon why it's called that. "The extinction of the human race," I thought. "Yeah right, I thought I was the only one left," But then I frowned. "Until I met that strange kid about a few weeks ago."

(Flashback: 4 weeks ago. Normal POV)

Bloodlust was laying down on his bed in his room wondering what he could do. He had finished reading some of his books, except the one about The Great Mushroon War. He was about to go ahead and read it until his watch communicator started beeping. He sat up and pressed a button to see a hologram of Hunson Abadeer's face.

"Bloodlust I need you out here in the courtyard now!" He said with a bit of anger in his voice.

"Of course Master Abadeer. I'll be right there." Bloodlust spoke nonchalantly.

He immediately got up and exited his room with his sword in it's scabbard on his back, running down the hall to the courtyard. When he stopped, he reached a dead end but waited for his master to opened the secret door.

(Finn's POV)

Thanks to our political rap, me and my bro Jake got the demon's to rise up against Marceline, who was being controlled by her dad's Nightosphere Amulet. We were being carried by the demon's, getting closer and closer to her until we were grabbed and pulled aside. It was Hunson Abadeer you did it and was trying to stop us.

"Your not gonna get that amulet Finn! Marceline needs to take over the Nightosphere." He said glaring at us.

"No way man, she doesn't even want to!" I said telling him the truth, again.

"That's bulderdash baby. The amulet is filled with chaotic evil. She will learn to control it. And besides, she's my daughter! I just want her to make me proud."

"You should be proud already. Marcy is a great person and a great friend!" I said still trying to convince him to stop all of this crazy stuff. "And I'm going to save here by getting that amulet off her."

He merely laughed after I said that. "I'd like to see you try. But first," He then walks over to a nearby lever on the wall. What was he trying to do now? "Your going to have to fight my apprentice." He pulls the lever down and a secret door slowly lift up. "He is far more stronger than you. There's no way you can beat him!"

"Oh yeah? Well we'll see about that!" I said bravely and confidently.

I looked around for a weapon and luckily there was a sword with a root handle nearby. I stood ready to fight whatever he's got from the other side of the door. I can hear the clanking of gears from the door being open. Jake stood ready as well making his fists slightly bigger.

"I wonder what's behind that door?" Jake asked.

"I don't know man but we're about to find out. Look!" I answered him, pointing at the door.

The door was open and everything had gone quiet after the gear sounds had stopped. It was dark on the other side and we couldn't see anything at all. We waited only a couple of minutes and saw a foot step out from the shadows. Then we saw a guy step out wearing a white shirt with red and black lines on it, a dark red unbutton shirt, black cargo pants, and white and black shoes. He obviously was older than me by his appearence. He had black hair, a scar on his left eyebrow and right cheek, he was slightly tanned, and... human? He was a human! I couldn't believe it, so there were still more humans. Other than Fionna and Gary of course. I breathed a small queit sigh, seeing as he didn't have any gills like the Hyoomens. I just stared at him through my paper-mask with my mouth open, so surprised that he was a human. Then he chuckled after looking at us. He turned to Hunson and looked at him like he was crazy.

"Are you kidding me? You sent me out here to kill a kid and his pet dog?" The older human said to Hunson with a small smile.

"No, DO NOT kill them. I just want you to get them through that portal," The Lord of Evil then pointed to the hole leading to our treehouse. "So I can banish them and close the portal for good."

"That's it? Don't tell me your getting soft Master?"

"Don't you dare insult me apprentice or I'll send you in the firepits for 4 hours!" Hunson sounded somewhat angry toward Bloodlust.

"Wow that's 3 hours LESS than last time. Calm down Master Abadeer. Don't get your boxers in a knot." He then turned his head at us and gave a sinister smile. "I'll take care off these two."

I still held my sword in my hands in a defensive stance. I turned to look back at Marceline fending off the demons and then I look at Jake and said, "Jake, go help Marcy. I'll handle this guy." I looked back at Bloodlust, glaring at him. "Dude are you sure you can handle this guy?" Jake said worriedly. "Yeah man." I replied without taking my eyes off of the human in front of me. "All right bro, be careful." Jake then ran towards the crowd of demons and the warped Marceline.

"So, it looks like it's just you and me then." He then unsheathes his sword from his back. His blade was red with a gold handle that had black runes on it. "Strange sword." I thought.

"You know, I'm just as surprised as you are. Seeing another human. Big moment for us both huh?" He looked up and down at me. "Well better take a long look at me, because I might be the last human you may ever come across. Now then, this will end quickly." His voice sounded cold and evil when he said that last sentence.

"Yeah, for you!" CLANG!

As fast as lightning, we charged at each other with our swords clashing together. "Such a pathetic sword you have. You can't possibly do anything to me with that." He shove his sword forward, pushing me back. "Oh yeah? Well what's with those stupid drawings on your sword?" He lifted his sword up. "The runes are enchanted with the souls of a thousand cursed souls and demons, giving it special elemental powers." The runes glowed and his sword caught on fire. With each swing in the air, a fireball got shot straight towards me. Luckily I kept jumping out of the way doing cartwheels, avoiding every blast. When he stopped, he ran up to me with unbelievable speed and kicked me in the face. I flew halfway across the room. As I tried to get up, he kicked me in my gut knocking the wind outta me. I tried to breathe calmly in order to get back up. Fortunately for me, Bloodlust stayed put waiting for me to get up. When I finally got back on my feet, Bloodlust looked at me with a strange expression.

"How can you still keep going? Usually after I do something like that, my enemies stay down for the count accepting defeat." He said examining me like I was a weird being or something.

"Well I'm not your average warrior. So I bet you won't expect THIS!"

I ran up to, catching him off guard, and roundhouse kicked him in the side of his head. He stumbled back a bit but kept his balance. He looked at me with a crooked smile.

"Well... you were right. I didn't expect that at all. But too bad it didn't do you much good."

He charged toward me and started slashing at me. I tried to block but some of his attacks hit me, slicing my body. There were a few cuts on me, nothing too big but it still hurt and some blood was dripping down. I couldn't believe how skilled this guy was. "He has such unbelievable speed and strength. Who is this guy?!" I thought to myself, wondering what this guy really was. He came at me again but I was able to block his attack and kick him in his gut. I then took the chance to finish him with one blow. But he was fast enough to get out of the way in time before I could stab him or cut his head off. Although I did slashed at his left shoulder. He didn't even scream from the pain of that huge wound. "Maybe I was wrong. No way this guy is human." I thought, giving myself second guesses about the very skilled warrior standing in front of me.

"Impressive," He gave me a blank stare as he spoke and he had lost his smile. "I haven't fought like this in years." This time he gave a small grin at me. "Who are you? What's your name boy?"

I was about to tell him but Jake called for my help as soon as I opened my mouth.

"Finn! I need your help! I can't get to the amulet, these demons are in the way!" I looked backed and saw him fending off some demons, trying to get to Marceline. Before I took a step towards Jake, Bloodlust stopped me.

"So... your name's Finn huh?" He then looked at me funny when I looked back to him. "Strange name for a strange kid." He looked at the group of demons, at Jake and Marceline. He then looked back at me and ginned widely. "Go and help your friends. I have a feeling we will see each other soon. Maybe not tomorrow or next week, but soon. We can put our duel on hold until then."

I glared at him like he was a sick twisted monster, which in fact, I thought he was, in my opinion. I dropped my sword and was about to run to Jake's side. But then I stopped and hesitated before I said to Bloodlust,

"Hey why don't you come with us back to Ooo? You can be free from here."

"Free?" He said looking at me confused "Why would I need freedom?"

"Because I think you need it man. You can live a new, better life." I answered him smiling at him. Why was I being nice?

"A new... life?" He still looked at me a bit confused.

"Yeah man." I looked over at Jake to see him still fighting the demons "Hey I gotta help my friends. You can with us if you want, your choice." I said still smiling at him.

After that, I ran to Jake and started to fight off the demons with him. I still didn't really know why I was being nice to that guy. Maybe it was because he deserves better. Maybe... he was almost like me.

We managed to get through the crowd of demons and get to Marceline. We both got on her back as I started to rip off the amulet. As soon as I did, Marceline exploded into black goo. But luckily, she was fine as I held here up in my arms. I looked at the goo and the demons in it. They started to eat it like how me and Jake eat Treetrunk's apple pies.

"Ugh, that's sick man." Jake groaned looking at the demons.

Suddenly the demon's started to bite on Jake's legs that were somewhat covered in the black goo. "Ahh their eating my legs!" Jake screamed in pain. I couldn't think of anything to try and make the demons stop. But then I looked at the amulet. A crazy idea got in my head. Without hesitation, I put the amulet around my neck. "Dude no!" Jake tried to warn me but it was already too late.

(Bloodlust's POV)

I looked at the group of demons as they ate the black ectoplasm. Then I looked toward the boy named Finn and his dog friend named Jake. I saw what only very few people would've done. He put on the Nightosphere amulet. As I watched, I saw the group get flown back being slammed into the walls. I saw that Finn had transformed into a soul sucking demon like Master Abadeer in his form. He had white skin and white eyes with pinkish-purple slime hanging off of him. He had the black business suit on with a red tie and red boots on. He tossed Marceline and the dog into the portal leading into a house. I saw Marceline wake up as Demonic Finn tried to speak.

"Marceline... no one... LEAVES THE NIGHTOSPHERE!" He shouted as he reached to grab Marceline and Jake.

He was about to grab them but Hunson Abadeer came up from behind and ripped the amulet off of him. He then tossed Finn through the entrance. He put the amulet on and was wearing the usual business attire. After what looked like Jake had tried to shield her, they both looked at Finn.

"Marceline!" Hunson yelled from in the Nightosphere. He tried to cover-up his plan by saying, "Uh... what happened to him? Kids these days. Am I right?"

"Dude, seriously." Jake said staring Hunson knowing full well of his plan to have Marceline rule the Nightosphere.

"Dad I can't believe you did that." Marceline said frowning at her father. Hunson simply gave an innocent smile to his daughter. "Dad that sucks!"

"I know I'm sorry. I just thought, you know, if you took over the family business, you'd want to make your old man proud."

"Yeah I want you to be proud. I want you to be proud of me!" Marceline glared at her father upon saying this. At that moment, Hunson finally realizes why his daughter never wanted to rule the Nightosphere.

"No I didn't mean... Marceline, of course I'm proud of you." He said sincerely with his smile already gone.

"Dad..."

"Your friends, they're all right. And that political rap, pretty great!" He said giving his daughter a thumbs up give her a big smile.

"All right all right, I gotta go dad. See ya later!" Then Marceline motions her hands to close the entrance. "Marceline, she never ceases to amaze me." I thought to myself grinning.

Then Hunson turned around with his smile gone. He walked toward me glaring at me. By then, I had already dropped the smile and just stared at my master. He stands tall in front of me, still glaring and says,

"Your lucky that things between my daughter and I are better. Or else you would've been in the firepits for 10 hours while getting a lashing!" He said with slight anger in his voice.

"I'm sorry Master Abadeer." I took a small bow to him. I was about to say something else but kept my mouth shut. I could easily handle whatever Hunson threw at me now but I didn't want to take that chance. I had better things to do then get tortured some more. Then he stopped glaring and started smiling at me.

"Well, you did help. I'll admit that. So your free to do what you want today. But by midnight, I expect you to be in your chambers. Or else." He then dropped the smile when he said those last words warningly. I smiled and took another bow saying,

"Of course. Thank you Master Abadeer."

"Good, now go to the infirmary and get that wound healed." He pointed to the slash mark on my left shoulder.

"Yes Master Abadeer."

He then walked away and back into the kitchen to get something to eat. I bet he was famished. And so was I. But food would have to wait for a while. I looked up at where the entrance was and stared at it. "Finn the Human," I thought, "Your a strange kid. But this isn't over. We will finish what we started. And you will lose, dearly."

(End of Flashback. Present day. Bloodlust's POV)

"Freedom," I thought to myself, staring up at the ceiling. "A new life." I scoff and shook my head as cast those words out of my head.

"Stupid kid, I'll never be free. No matter what I do." I said quietly.

I looked over to my backpack by my bed and got an idea. "Although," I thought again grinning. "I will take his offer on going to this land called Ooo. And I know exactly how." I remembered one day while I had my free day to roam around the Nightosphere and the Abadeer house, which I get only once a month, that there was a portal next to the living room. I never thought about using it because of two reasons. One: Hunson warned me that he would torture and punish me for trying to escape. Two: I never knew where it would take me, until now that is. Now that I know where Finn is, we can finish our duel so I can, in a more understandable term I like to use, kick his ass. Anyways, lucky for me tomorrow is my free day.

(The next day)

As soon as Hunson leaves to wreck havoc on the inhabitants in the Nightosphere, I took this opportunity to commence my plan. I had everything I needed. I had my sword, my black backpack full of food, some pairs of shirts and jeans, rope, a few books especially the "Great Mushroom War" book, and a compass. I figured that's all I would need to survive. Even if I just had my sword I would be all right. I walked into the house, which was in a mountain, of the Abadeer family. I've been in here quite a few times. I've been in the family library, Marceline's room, almost every place in the house.

As I was walking into the living room, I looked out the window over looking the Nightosphere. "So much chaos," I thought. "I'm actually going to miss it."

"But my love for fighting comes first." I said cheerfully. "I just hope this Land of Ooo will amaze me or else I'd just be wasting my time."

I walked out of the living room and started heading towards a nearby wooden door that has the portal on the other side. Suddenly I stopped in front of the fireplace. Up on the mantle, hanging over the fireplace, was the Abadeer Family sword. It had a grey colored blade with a handle carved out of bones with a small skull on the butt of the handle.

"I would love to take that sword with me. So who's going to stop me?" I looked around to see if anyone was watching. I took the sword off over the fireplace, slipped my backpack off, and wrapped the strap on the scabbard around me over my sword. I put my backpack back on and continued to walk towards the door. I opened it to see the blue swirling vortex in the floor. Without hesitation, I jumped in prepared for whatever is on the other side. Prepared for a new life, as Finn would've said.

"Ready or not Finn, here I come." I thought smiling to myself.

Well I just want to go over a few things.

I hope all of you viewers enjoyed my first fan-fic. I hope everyone reviews, either good or bad, so I can know what to fix. Also you can tell me what I should add. If I think it would fit with the story, I'll do so.

Next thing I want to say is that I hope these authors read and review my story:

DubbleDualSword, Gary the Human, Aranhpaz(Recently changed to Invader Deb), ZalgarTheLostHero(Recently changed to William Elric) , dinoRAWR, Marceline45(Recently changed to Rosalie777) ,Collector Zero, wiseguy1107, zengods, and Master Creator Rin. These authors, in particular, are some of my many fav authors of Adventure Time. If you haven't read any of their stories, I suggest you do so.

Also If any of you has read Gary the Human's Blog Time fic already, don't overreact. I asked if my OC could be on his blog time fic before I posted this story. I also asked if I could use his OC in mine and he said yes. Thanks again Gary the Human.

And that's it. So anyways plz review and I'll keep posting more of First Blood, First Kill. Thanks all!