Hello everyone! Here's chapter 10 for you guys! This is gonna be a multiple part thing for the next couple chapters, with Finn running around Ooo showing the people what he's capable of.

Enjoy! And of course, I do not own 'Adventure Time'.

Chapter 10

Finn's Endeavor (part 1)

"No Football! I will never let you take control!" BMO yelled into the mirror.

"You cannot escape me BMO, everywhere you go, I will follow." his reflection replied.

"I am in control Football! You will stay in the mirror!"

"I hate the mirror! The only form of entertainment I get is watching Finn take a-"

BMO and Football heard a scream, BMO gasped. "Finn!" The little robot jumped off the stool he was perched on and ran out of the bathroom.

BMO hurried up to the bedroom where he saw Finn sitting up on his bed panting and shivering, he looked terrified. BMO crawled up onto the bed. "Finn! What is wrong! Why did you scream so loud?!"

Finn didn't respond right away, he just sat there for a minute staring into oblivion. The terror in his eyes then subsided a bit and Finn looked at BMO, the friendly little machine looked pretty worried about him. Finn let out a long breath. "Everything's fine BMO, it was just a nightmare." Finn said, but he didn't sound too convincing.

BMO gave a worried frown, then walked up and hugged Finn's arm. "It is okay now Finn, you are okay now."

Finn smiled at BMO's compassion, he gave the robot a pat on the head. "Thanks BMO."

BMO walked up over to the foot of the bed. "Now get up! You are going to kick butt and take names today with Jake!"

A few minutes later, Finn was standing outside the house fully clothed waiting for Jake. Finn was having a hard time getting the horrific images from his nightmare out of his head, it might have been a dream but it had felt so real.

"Hi Finn!"

Finn looked over to who had spoken, the water nymphs were waving at him from the pond. Finn walked over to them in hope of forgetting about his nightmare. "Hey girls." he greeted with a smile. "How's it going?"

"It's going good." the short haired one said. "What are you up to today?"

"Oh I'm going with Jake to venture through a dungeon and beat up a troll or something." Finn answered. "I'm not really sure, Jake didn't really give me a lot of detail."

"Oooo, I bet you'll do great." the one with lipstick said. "We heard about how you beat up that grass ogre who was harassing Tree Trunks."

Finn tilted his head. "Really? Word sure does spread pretty quickly here in Ooo huh?"

"You've become a pretty popular topic of interest Finn." the one with the ponytail explained. "You're all anybody talks about anymore, I've even heard the wizards of Wizard City have taken an interest in you. 'Presto' they call you."

'Oh… not sure if that's good or bad.' Finn figured his friendship with Ice King would be beneficial whenever magic was to be involved, but if the wizard society was keeping tabs on him… Finn wasn't entirely sure what to make of that. "Why do they call me Presto?, that's just a name I used to trick the Ice King so I could save the princesses. Don't they know my name is really Finn?"

Ponytail nymph shrugged. "Probably, but if there's one thing a wizard loves to do, it's show off with some pizazz. My guess? They know your learning fridjitzu, so they marked you with the name 'Presto' just because it sounded wizardy. Your becoming an icon and the wizards want a say in your reputation. 'He knows magic, we did that y'all.' is most likely what they're trying to advertise."

"Huh, okay then." Finn wasn't really sure what to make of that either. If Finn's reputation was getting so widespread then it made sense some groups would want to affiliate with him. 'I wonder if that's what Flame Princess is trying to do with inviting me to that festival.' he couldn't help but wonder. "Hey wait, how did you know I was learning fridjitzu?"

The nymphs looked at each in slight alarm.

"Oh, uhhhhh."

"We hear a lot of things… water nymph connections and stuff."

"Yeah we totally don't spy on you through the windows, that would be just creepy right?"

Finn blinked in confusion. "Umm… yyyyeah, I… guess it would." He decided to change the subject. "So listen, I don't think I caught your guy's names. If we're gonna be neighbors, then I think I should at least know your names."

The three nymphs blushed a bit, the one with the short watery hair was the first to recompose herself. "Well, my name is Merry."

The one with lipstick raised a hand. "I'm Cherry."

The ponytailed one raised her hand. "And I'm Sherry."

Finn couldn't help but grin with amusement. "Seriously?"

Merry rolled her eyes. "Yeah yeah, we heard all the jokes so do you worst."

"Incoming!"

Finn turned in the direction of the voice only for something to crash into him, knocking him to the ground. That something turned out to be Jake, he sat on Finn's chest and dusted himself off. "Hoooo-wee! Sorry 'bout that man, I knew I was running late so I slingshot myself over here from Lady's place."

"It's cool man, no harm done." Finn wheezed, his voice barely audible.

"Heh heh, good to hear man." Jake got off Finn and helped him up. "So, you ready to go have some fun? Or you wanna stay with these water nymphs and do the same? Either way it's cool with me, you wanna stay with the nymphs than I totally understand."

The nymphs giggled, earning a blush on Finn's face. "Let's go." he said.

"You got it bro!" Jake inflated into the size of a van and placed Finn on his back, then he elongated his legs. Jake turned his head to Finn. "Hey Finn, you know what time it is?" he asked.

"I think it's around eight or nine." Finn responded.

"No! Well I mean yeah, it's eight thirty but that's not what I meant." Jake stretched his hand up for a fistbump. "It's adventure time yo!"

Finn gave Jake a fistbump. "Heck ya, adventure time!" he turned to the water nymphs. "Bye Merry, Cherry and Sherry!"

"Byyyye Fiiiiiiinn!" the nymphs shouted with a wave before Jake carried Finn off.

'Adventure time… that has a nice ring to it.' Finn thought.

"So you're on a first name basis with the nymphs huh?" Jake teased as he carried Finn across the Grasslands. "My man."

Finn rolled his eyes, "Come on man they're my neighbors, I figured it was only courteous to get their names."

"Uh-huh, sure pal, sure." Jake said with a grin. "You oughta be careful with those nymphs though man, they don't call it 'nymphomania' for nothing."

"What's that?"

"Ohhhhh… uhhhhh… well… I'll tell ya later."

Finn just shrugged, figuring it was just another weird Ooo thing. "So where we headed?"

"Oh yeah! See, there's this dungeon hidden in the forest I've been meaning to check out. It was on a holo-message my dad left me, according to him it used to be the hangout of a famous thief they called the Shadow Thief, 'cause no one could catch him. He ended up retiring in his dungeon crib full of stolen loot, that was decades ago though so he's probably dead by now. Dad never got around to finding it when he was alive so I figured I would give it a go, I was gonna take my granddaughter Bronwyn, she's been asking me to take her on a few adventures. But I figured if I just take you, I won't get an angry phone call from Kim Kil Whan."

Finn's interest certainly peaked. "That sounds pretty rad, but if the dungeon is just the Shadow Thief's retirement home, then how dangerous can it be?"

"Well, the other reason they called him the Shadow Thief was because he also practiced a little bit of dark magic. I don't think he was an expert, just a few things he picked up to help with his thieving career. But still, best be on your guard."

Finn and Jake eventually made it to the forest area, Jake walked above the canopy looking down at the foliage beneath him. "Hmm let's see, where did Dad say it was? Man, kinda wish I brought that holo-message with me. Oh wait a minute, I think I see it!" Jake shrunk down to the forest floor and Finn jumped off onto the ground. In front of them stood a rock carved into the vague outline of a woman covered in vines. "Dad said 'the entrance to the shadow's lair is found within the lady's stare.' Not sure why he couldn't have been more specific instead of leaving me with a dang riddle, but that's Dad for you." Jake stretched up to the stone lady's face. "The lady's stare? She doesn't even have eyes or anything."

He knocked on the head. "Let us in dangit!" Nothing happened. Jake rubbed his chin in thought. "Hmmmm, maybe I gotta take a different approach." Jake moved to the rock's side and draped an arm over the lady's neck. "Hey baby, you lookin' fine." Jake said in a sexy voice. "How's about you show me your place huh?"

No response.

"Come on girl, don't make me beg. Show me the door to your place and we'll make some magic happen."

No response.

Jake grunted in frustration and stretched over to Finn's side. "Man this chick is cold, that normally works."

"Well as… interesting as that was to watch, you mind if I take a whack at it?" Finn asked.

"Oh! Are you saying we should smash it?!" Jake asked with a raised, inflated fist.

"No no no! Just let me take a look at it!" Finn shouted.

Jake deflated his fist. "Alright, go nuts."

Finn walked up and examined the stone. It had no distinguishable features, it looked like it had been sculpted years ago and time has been wearing it out ever since. 'The entrance to the shadow's lair is found within the lady's stare.' "Hmmm." Finn tried to picture the stone lady with a pair of eyes. 'The lady's stare… what is she staring at?' Finn pictured in his head the stone's imaginary eyes and followed their line of sight. It led him to one of the trees, there didn't seem to be anything special about the tree. Finn walked around and examined the tree in hope of finding something.

Jake stared at him in confusion. "Finn, what are you doing? The stone's over there."

"Yeah I know, I'm just…" Finn looked up and saw a short low hanging branch, an arm's length away from him. 'I wonder…' Finn jumped up and grabbed the branch, it bent but instead of snapping there was a click sound. A faint tremor could be felt in the ground and the section of earth the stone sat on opened up like a giant submarine hatch.

Jake's went wide. "Holy ham! You did it!"

Finn walked over to the dungeon entrance. "By the looks of it, I would say I did it as well." he responded with a smile.

Jake hurried over to Finn's side and looked down the hole, he took a sniff and formed a sour look. "Ew, something's down there man, it smells hecka evil in there." the dog then grabbed Finn's arm. "Okay bro, on the count of three we jump. One… Two…"

"Wait a minute, there's a ladder right there we can-"

"Three!" Jake jumped into the darkness dragging a screaming Finn along with him.

Before they could hit the ground Jake transformed into a parachute and the two of them gently floated to the bottom. It was pitch black in the dungeon, neither of them could see anything beyond the light that descended from above through the entrance hole. Once they were on the ground, Jake walked over and began to feel against the stone walls to the side.

"Jake, what are you looking for?" Finn asked.

"A light switch or something."

Finn raised an eyebrow. "Jake, we're in a dungeon that may very well be hundreds of years old. There is no way your gonna find a-"

"Found it!" (Click)

To Finn's surprise, torches on the walls lit up in sequence from one end of the large hallway to the other. It was a simple stone hallway they were in, nothing fancy. Just a long arched walkway to a wooden door on the other end.

Finn stared down the hall skeptically. "Okay, although this may look simple enough, I think we can both agree that there's a trap in here."

"Oh yeah, absolutely." Jake answered. "Let's go!"

Finn and Jake were halfway down the hall when something did indeed happen, the shadows cast by the fires merged together on the floor in front of the two dungeon crawlers. The shadows formed a duo of eight foot tall knights, they were armored and armed with greatswords and shields, their entire bodies looked like they were carved from obsidian, two balls of bright blood red fire functioned as their eyes behind their helmet's visor.

Jake pointed. "See what'd I tell ya? Dark magic yo."

Moving in perfect unison, the Night Knights (ya like that?) raised their weapons and charged at Finn and Jake. Jake brought one knight down with a giant fist that sent the shade flying to the other side of the hall, Finn summoned a pair of ice ninja stars and threw them at the other knight's eyes, hitting the flames point blank. The Night Knight dropped his sword and covered his eyes with his hand with a ghostly moan of pain before dissolving away into nothing.

Finn and Jake ran to the wooden door at the end of the hall but the Night Knight that Jake pummeled was still alive, he glared at Jake with intense burning eyes. Before the knight could retaliate though, Jake stretched around and hogtied him with his own body. The shadow struggled against the magical dog's hold on him, Jake was doing his best to hold him in place. "Finn!... finish him off!" he shouted in a strained voice.

Finn summoned his ice twin sai and leapt at the knights head, he stabbed the shade in his fiery eyes and the creature dissolved as the first one did. With the Night Knight gone, Jake resumed his normal shape and size. "Phew! Good job Finn! You're doing pretty good for your first dungeon crawl."

Finn dismissed his twin sai and smiled. "Thanks man. I gotta say, that was one heck of a rush. I like it!"

Jake chuckled. "Oh yeah? Well lucky for you, we're just getting started." Jake smashed down the wooden door and ran through with Finn in tow, they entered a large, torchlit square room big enough to hold a house. A stone stairway led up to another door on the opposite side of the room, but it wasn't going to be that simple of course.

The shadows once again morphed into solid form, only the two figures that stood to oppose Finn and Jake were obviously much more dangerous than the Night Knights. One was a shadow giant, a dark, hulking behemoth capable of crushing a man with just a stomp of his foot. The pitch black giant wore no armor except a great helm of shadow, the helmet's visor was designed in the shape of a fanged demon with two eyes of blue fire.

The second shade seemed even more dangerous, he wasn't a giant but he stood tall and strong, a couple feet taller than Finn. His jet armor appeared to have been well crafted, like something a king's champion would wear. His skin was even darker than the Night Knights had been, like squid ink in the dark. His visored helmet was crafted into the shape of an obsidian skull with a pair of ram horns, his eyes were two purple flames that burned with malice. A longsword as black as a starless night sky was gripped in his hand.

It should have terrified any man with the sense to be afraid, but Finn felt no fear. "You take the big guy and I'll take the swordsman." He told Jake with determination.

"Woah, take it down a notch Finn. I don't think you should even try to take that guy on your-" the giant picked Jake up and tossed him against the wall before he could finish.

"Jake!" Finn shouted, he moved to help but the swordsman stepped in his way.

"You trespass in the lair of my master." the sword wielding shade said in a scary whisper. "You and your companion shall die here." The creature raised it's blade, ready for combat.

Finn summoned his ice katana and poised for combat as well. "Okay then, let's do this."

Finn and the shade rushed at each other, their blades met with a chilling clang of ice and shadow. They tested each other's strength, the shade was obviously much stronger. It pushed Finn away and took a swing, which Finn dodged and returned with a slice of his own, only for it to be blocked as well. It continued like this for a while, each fighter obviously skilled with their blade. The shade was quick as a cobra despite his armor, his double bladed sword delivering and trading blows with expert skill. Finn was holding his own quite well, he moved quickly with no armor slowing him down and his blade was made for quick and powerful strikes. The fighters ceased their attacks and circled each other, their weapons poised and ready.

"I have waited a very long time for someone with skill to dare enter my master's lair." the shade said in his creepy whisper. "You have been the best entertainment I have had in a long time."

Finn's brow furrowed in anger. "Entertainment?! How about you quit playing and fight me with your all?!"

"As you wish."

The shade rushed at Finn and bombarded him mercilessly with a flurry of attacks. Finn could barely keep up, he was putting everything he had into blocking each blow. The shade managed to back Finn up closer to the corner of the room, with one powerful swing of his blade he shattered Finn's katana of ice into shards. Before Finn could react though, the creature backhanded him into the corner. Finn slid to the ground in a daze, his vision was a painful blur and a purple bruise formed on his face where he had been hit. Finn blinked his vision back and saw the shade standing over him. The creature allowed Finn to stand back up, figuring he had won by the sight of the wounded boy.

"Die with honor, as I did." the shade raised blade.

Finn brought his hands together.

"Die alone… as I did."

Finn mumbled a chant and disappeared in a burst of snow as the blade came down. The sword hit the ground with a clank, the shade stared at the spot Finn had just stood in.

"Where'd he go?"

Finn reappeared behind the shade in a snow burst sword in hand and cleaved the shade's head clean off.

"I'm right here."

The shadow's head fell to the ground with a thud, it rolled until the fiery eyes landed on Finn.

"Thank… you." were his final words before the body and head dissipated into black smoke.

Finn took a few breaths. "Don't mention it." he then looked over to see how Jake was doing. The dog had his body wrapped around the behemoth but the monster had Jake's head on the ground and was repeatedly stomping on it, earning a loud 'ow' from Jake.

"Ow! Ow! Ow! Ow! Ow! Ow! Finn! Help! Me! Ow! Ow! Ow! Ow!"

Finn ran up and summoned a throwing knife which he then chucked into one of the giant's eyes, who in return brought a hand to it's eye and stumbled backwards in pain, releasing his hold on Jake.

"Oh thank glob. Alright big boy, my turn!" Jake stretched up and uppercutted the behemoth with a giant fist. The monster fell on his back with a loud crash with Jake wrapped up tightly around it, while it was down Finn ran to its head. Finn stood over the remaining eye, raised his blade, and jabbed it into the fire. The blue flame went out and the giant's body dissolved into smoke.

With the two shades gone, Finn and Jake took the chance to finally catch their breath. They were both bruised from the fight and they stood there panting from exhaustion, the panting however, turned into light laughter.

"That was… intense." Finn said between breaths.

"Yeah… I saw you freakin' disappear back there… when you were fighting that thing… didn't know you could do that." Jake replied in the same manner.

"Oh that?... a technique I read in IK's book… I never tried it out so… so I'm glad it worked the first time."

"Heh heh… me too man."

Finn and Jake finally got their bearings back and walked over to the staircase. "What do you think is behind that door?" Finn asked.

"That's probably where the loot is, dungeons normally leave the toughest monsters for the end." Jake answered. "You know, like a video game."

"What if there's just an even tougher monster behind that door?"

"Try to think positive, will ya?" Jake said before stretching up the stairs to the door, Finn walked up the stairs to his side and they looked at the door. Jake slowly opened it and Finn brought his sword up ready for action. They peeked inside, it looked like a dining room. A long table sat in the dark room, the only source of light were the table candles glowing with blue flames. At the end of the table sat a dead guy in a fancy wooden chair, a mummified man with dried, papery skin wearing a torn and faded black cloak.

"Oh my glob." Jake walked over to the dead guy. "Dude I think this is him, this is the Shadow Thief!"

Finn walked over to the other side of the dead guy. "Really man, are you sure it's him?"

"Who else could it be? Oh man, this is so cool!" Jake shouted.

Finn shushed him and glanced around nervously. "Dude keep your voice down." he said in a hushed tone.

"Pssh, what am I gonna do, wake him up?" Jake jerked a thumbs towards the corpse.

And the corpse grabbed Jake's arm.

Jake let out a scream and clocked the mummy right in the jaw, which fell off and landed on the table. The dead guy released Jake, picked his jaw back up and reattached it.

"OW! What the stuff man?!" the mummy asked angrily.

Finn and Jake took a frightened step back. "You're alive?!" Jake shouted.

"If you call this living." The mummy gestured at his state. He sounded like he could have really used a drink of water.

Finn gulped. "Are… are you the Shadow Thief?"

"Once upon a time, people called me that." the former thief leaned back in his chair, empty eyes staring at nothing in particular. "Oh those were the days, I robbed nearly every part of Ooo. Never went to the Slime Kingdom though, that place is gross. Is it still gross?"

"Incredibly gross." Jake answered.

"Yeah, that sounds about right."

Finn stared at the mummified man in disgust. "Dude, what happened to you?"

The Shadow Thief let out a sad sigh. "During my early days as a thief, I came across a warlock who offered to teach me the dark arts. I was skeptical at first but curiosity got the best of me and I agreed to his teachings." He looked Finn in the eyes. "That… was a mistake."

Finn and Jake moved in closer, obviously intrigued. "I spent an entire month learning dark magic from the warlock, after I learned stuff like phasing through shadow, reading and controlling minds, and shade summoning, I went back to the thieving business. I stole enough scratch to live like a king till the end of my days, but I wanted more. I wanted more treasure, I wanted more power, mine was a cup with no bottom. So I tracked down the warlock that taught me what I knew… and killed him in his sleep."

Finn and Jake's eyes widened. "Holy stuff man!" Jake exclaimed.

"Well… was he evil at least?" Finn asked.

"Whether he was a saint or a monster, it made no difference to me." the Shadow Thief said, his voice becoming quite sad. "I killed him and took his book of magics, and I learned to do all kinds of things. You must have seen the shades I left in my dungeon yes, I made them. The swordsman even contained the soul of a warrior I killed a long time ago, I corrupted his soul and made him mine." The thief's hand clenched into fists. "There was one spell in particular I found very interesting, it was a spell that could allow you to live forever. And like any fool, I was beyond eager to use it. 'The Immortal Shadow Thief' I thought to myself, well." the dead man gestured to his face. "Fill in the blank."

"Dude." Finn said sympathetically. "How long have you been down here like this?"

"Hundreds of years, maybe thousands, I didn't really keep track. The spell bound me to this place, I have spent so long in this dungeon all alone. The spell took away my ability to use magic, so even if I did find a way to reverse the spell I couldn't use it. I ended up burning that book, wishing I had never even became a thief. I can't die, and I am not alive." The cursed man grabbed Finn's arm. "I beg of you, end my torment. Please!"

Finn pulled his arm out of the Shadow Thief's grip. "How am I supposed to do that?"

"The book gave only one solution. Someone else has to kill me, I need one of you to kill me."

Jake raised an eyebrow. "If your ace in the hole is someone coming in here and killing you then why did you have those shadow guys guarding the place?"

"The spell took away my ability to use magic, I couldn't get rid of them once the spell was complete." The cursed thief looked at Finn. "You have a sword, take that thing and slice my head off. Do it, please!"

Finn stared at the former Shadow Thief. "Okay, I'll do it. On one condition."

"Yes fine, anything!"

"Tell us where your loot is."

"You want it? You can have it!" The cursed thief clapped his papery hands and the wall behind him opened up like a double door. Finn and Jake walked over and their jaws nearly hit the ground. Beyond the secret door was a room filled with gold, silver, jewels and gems, there was so much treasure you could swim laps in it. "Take it! Take it all!" the Shadow Thief cried. "It's brought me nothing but torment!"

Finn turned to the thief, who remained seated in his chair. "Is it cursed or something?" he asked.

"Only to me it is." the thief replied. "I gave you my life's work, now give me my life's end."

Finn walked over to the cursed man, he raised his ice blade ready to deliver. "Are you sure you want this?" he asked uncertainly.

"More than anything." the thief answered, his tone was enough evidence to prove he was telling it true. "Word of advice kid; if anybody offers you eternal life, give them the finger." The legendary Shadow Thief closed his empty eyes. "I am ready."

Finn nodded. He took a deep breath, and brought an end to the Shadow Thief's life. After the job was done, he walked back over to Jake's side and stared at the loot.

"You okay man?" Jake asked.

"Yeah I'm fine, really wish I didn't have to do that, but I'm fine."

"Okay then. Ready to grab this loot and scram?"

"Absolutely."

Finn rode back to the treehouse in a Jake dump truck loaded with treasure, when dump truck Jake stopped outside of the house Finn got out and looked at all of the treasure in the back. "Where am I supposed to put my half? That's a lotta loot."

"I'm on it, open the door for me." said Jake. Finn did as he said and the dog transformed into a large funnel and funneled half of the treasure into the treehouse foyer. Finn walked up to the entrance and looked into the now treasure filled foyer. "Dude I can't just leave it here, I would get robbed left and right." he told Jake.

Jake resumed his normal stature while leaving a flesh cord attached to his body truck of treasure and walked to the entrance. "I wouldn't worry about it man, your landlord is the freakin' Vampire Queen and this is Candy Kingdom territory. No one's crazy enough to try to steal from this place." Jake stretched out his arms and cleared a path to the ladder leading upstairs. "Easy to grab and go when you're down for some shopping."

BMO's head popped up out of the pool of treasure. "Oh no, do not worry about BMO, he is fine." the robot commented bitterly. BMO then picked up a silver chalice and a gilded dagger. "Ooo these are nice. Finn, what are you going to do with all of this treasure?"

Finn shrugged. "Don't know, guess I'll just leave it here for now." he checked the time on his phone. "Huh, it's only half past noon. What do ya wanna do for the rest of the day Jake?"

Jake rubbed his chin in thought, then his belly rumbled.

Finn laughed. "You wanna get a snack?" he asked.

"Oh that wasn't my gut, but a snack sounds good though." Jake reached into stomach folds and pulled out a ringing phone, which he answered. "Hello who dis?... uh-huh… uh-huh… oh ya don't say… alright I'll be right there." he hung up.

"Who was that?" Finn asked.

"The Wildberry Kingdom is being attacked by a two headed giant. You ready for another brawl?"

Finn smiled. "Absolutely."

End of part 1, hope you liked it! I've been playing a lot of 'Doom Eternal' so that may have been what inspired the final two shades in the dungeon. Kickass game by the way, I'd totally recommend playing it.

Part 2 will be with you shortly!