I decided to give the Ice King a rival and Finn & Jake another big challenge to overcome in this character that i personally made up simply called the Fire King. He's basically the physical opposite of the Ice King in every way, but has a similar personality. Imagine the Bubblegum Prince and Father from the K.N.D. mixed with short, nappy black hair and a trimmed beard to go with it. I may do more stories involving him, even though i'm pretty much doing this for fun. I own none of the Adventure Time characters or names (just Fire King lol). Also, this is my first fanfic so sue me if things don't sound right to you.
*One day, The Fire King decides to leave his smoke-filled kingdom and pay a "visit" to another, belonging to his counterpart. On his way to the ice kingdom (by flight), Finn The Human & Jake The Dog notice him from their front yard.*
Jake: Wonder what the Fire King's up to.
Finn: Whatever it is, it can't be good.
Jake: How do you know, dude?
Finn: Come on, man. When has the Fire King ever done anything nice for anyone but himself or his creatures?
Jake: Good point. And it looks like he's heading to the ice kingdom.
Finn: See? He's probably gonna start something with the Ice King. We should follow him.
Jake: Why? I thought we hate the Ice King.
Finn: We do, Jake, but the Fire King does even more. And it's my duty as a hero to see what he's planning.
Jake: Yeah, I guess so. Let's go.
*Somewhat reluctant, Jake helps Finn travel to the ice kingdom with his limitless stretching abilities. When they get there, they see the Fire King destroying random crystal glaciers with huge fireballs coming out of his hands.*
Finn: Hey! Flamebrain!
FK: (stops) That's the best you can come up with, Finn?
Finn: Not really. Yaaaaahhhhh!
*Finn throws some ice crystals at FK. The crystals sting him but nothing more as he shakes them off.*
FK: (growls) How dare you? Just stay out of this, human! This is between Kings, not some boy with foolish dreams!
Jake: Maybe if you tell us what you're doing here, we'll leave.
FK: Hmph. I don't see the point in telling either of you anything.
Ice King: Then how about telling me, Mr. Hot Stuff?
*Fire King, Finn & Jake turn around to see the Ice King was behind them, hearing their conversation.*
IK: Well? You wanna explain why you were destroying my home and waking up my poor pet Guenther?
*A short cry from Guenther, Ice King's pet penguin, could be heard in the background.*
FK: What do you think, old man? It's called domination.
IK: Oh yeah, sure. Destroying some helpless crystals that can't fight back. That's really scary, kid.
FK: At least I don't kidnap princesses and force them to love me!
Finn: Whoa, whoa, whoa. Take it easy, guys.
IK & FK: Oh, shut up! (both blast Finn & Jake into a small ice cave and continue to bicker)
Finn: (groans)
Jake: You all right, Finn?
Finn: Yeah, I think so. You?
Jake: You know it, baby! But we gotta do something about this.
Finn: You're right. One crazy king is enough. We need to get rid of one of them.
Jake: I assume you mean the one with red skin, right?
Finn: Doesn't matter to me, even though he is more of a challenge.
*While in the cave, they thought of a plan to banish the Fire King from all parts of Ooo, except of course for his kingdom. They both decided that it should be settled in an old-fashioned sword battle. Eventually, they left the small cave, broke up the continuing fight between the 2 kings, and explained the news.*
Finn: Look, Fire King, I don't hate you or anything, but me & Jake are tired of you always causing trouble.
Jake: The Ice King does a good enough job of that himself.
IK: You tell him, boys.
F&J: Shut up, Ice King.
IK: (growls)
Finn: So, I challenge you to a sword battle. And if you lose, you are not allowed to leave your kingdom…ever.
FK: And if I win this battle, I will go to whatever parts of the land I want without you two "heroes" interfering. Deal?
*Finn & Jake look at each other for a moment. Is this too risky? But then, they exchange looks of confidence.*
Finn: Deal.
FK: Good. And just to make sure no one has any ideas…
*Jake and Ice King end up trapped in a magical cage of fire. They both try to escape, but the heat is too intense even for Ice King.*
Finn: Jake!
FK: What's the matter? The hero doesn't want to play fair?
Finn: Grrr! You will pay for that. (draws his sword)
FK: You will pay for defying royalty. (Materializes a fire sword)
Jake: You can do it, Finn! He's no different from anyone else you've faced!
IK: Yeah, what he said. And hurry up with beating him. I'm feeling faint…
*As their sword battle began, it was back and forth. They both dished out and received multiple attacks from each other. Luckily for Finn, he was surrounded by ice and snow, so whatever burns he took, he would quickly rub some ice and/or snow on them to recover during battle. The Fire King is naturally able to heal from physical attacks, even though it took him a bit longer to heal from any clever snow tricks Finn made up. Realizing that Finn has a slight advantage, Fire King desperately thought of a distraction.*
FK: I can never understand why you help people who can care less about you.
Finn: That's not what being a good guy is about. It's about being honorable.
FK: Oh, please. Honor doesn't exist. Everyone has selfish desires. Heroes like you use words like honor, courage and goodness to hide your own flaws.
Finn: Says a person who cares about no one but himself. I'll bet that you can care less about your own kind.
FK: You dare to say such silliness? I help those who deserve it, not just any fools who may stab me in the back!
Finn: You're just scared of loyalty.
FK: What?
Finn: You heard me. You have no problems having anyone follow your commands, but you never made any friends because you know people probably wouldn't like you. In a way, you're just like the Ice-
FK: (explodes) Don't you even think about it! He pathetically looks for love that he will never get! I look for respect that i will earn!
Finn: Same difference, you ugly hothead! Just admit it, you and Ice King are more alike than you realize!
FK: You just failed your "friends" by saying that ridiculous comment! You lose!
*Fire King's sword tripled in size and he swung with all his might at Finn. From the sword came a small wave of fire that was coming at him. There was little to nothing Finn can do to defend this attack without major damage when all of a sudden, Jake somehow stretched out of his flame trap and at the last second absorbed the attack for Finn by wrapping him up with his own body, almost like armor.*
Finn: Jake, no! What are you doing?
Jake: (grunts) Don't worry about me, buddy…just finish this guy off. (faints)
FK: (breathing hard) You shouldn't have interfered, Jake. I actually like you. This is what happens when you have friends. Either you suffer or they suffer. Sometimes both. In the end, it's not worth it…right, hero?
*As Jake fell unconscious, Finn let out a piercing scream that could be heard from miles away. He charged at the Fire King, with a new, vengeful energy. He only wanted to make his opponent suffer with one good swing of his sword, no matter what would happen after that.
FK: Take your best shot, Finn. Your pitiful metal can't harm fire!
IK: Maybe not, but my MAGIC can!
FK: How did you-?
*Before he could say another word, the Fire King was wrapped in magical chains of ice. He screams in pain.*
IK: By the way, kid, the next time you try to imprison someone in fire, make sure to do it somewhere NOT near heaps of ice! Ta-Ta! (flies away)
*The Fire King did what he could to get out of his trap, but it was too late. He was too weakened to defend Finn's relentless attack. Finn sliced every inch of fire he saw, until it was reduced to smoke and sparks. Fire King regenerates, but he barely has the strength to stand on one foot.*
FK (breathes slow): Finn?
Finn: What?
FK: You do know you cheated, right?
Finn: I didn't tell anyone to fight for me.
FK: Like it matters…I've lost so I'm to stay in my kingdom forever, correct?
Jake: Yep, that's the deal.
Finn: Jake?
Jake: Whew! You sure know how to barbecue, Fire King.
FK (smiles): It's what I do. How did you get out of my cage, anyway?
Finn: Yeah, I'm sure the heat wasn't fun.
Jake: Nope, but it was like sliding through a melting keyhole. It took time to practice, though.
FK: You must really like this human to risk your life for him.
Jake: No, man, I love him. He's my friend and friends always do things for each other. He may be a handful to deal with sometimes, (*at this, Finn blushes a little*), but I'd follow him on any adventure.
FK: How sweet. (fakes throwing up)
Jake: Hey, you need to try it one time. You're so wrapped up with domination that you don't even know what friendship is. By the way, you ARE a lot like the Ice King.
FK: Yeah, keep bringing THAT up. Speaking of that old fool, how did HE escape my trap?
Jake: That's something you may wanna ask him yourself. You can follow him to wherever he went off to, but nothing else.
Finn: And to make sure you do that, we'll follow you, Fire King. Talk to him and no funny stuff. Since you're banished, you might as well make peace with him.
FK: Hmph, You really are a hero. You defeat me and just assume I'll do whatever you say.
Jake: Well, you are outnumbered, dude.
Finn: And I can go for another battle if you want.
FK: Fine. I'll talk to him. You better hope HE doesn't do anything funny, because I will react.
Finn: If he does, we'll deal with him, too. We're not exactly big fans of him, either.
FK: Yeah, but sometimes I wonder. Alright, I'm sure he went back to his palace to rest or play with his pet or something.
J&F: Guenther.
FK: Whatever you say. Let's get this over with.
*All three of them headed to the Ice King's palace. Finn & Jake forced him to knock on the door. After a few seconds of waiting, the door opens.*
IK: What do you want?
FK: Listen, you may not have heard, but since Finn, or should I say, all THREE of you, defeated me in battle, I'm no longer allowed to travel through this land except for my own kingdom.
*Ice King smirks*
FK: And since that's the case, I want to shake your hand to end this feud once and for all.
IK: Hmmm…let me guess, Finn & Jake are forcing you to do this?
FK: Pretty much, yeah.
Jake: And we're not leaving until you do.
*FK and IK both look at Finn & Jake sternly, but the heroes return the look back.*
IK: Let's get one thing straight, Fire King. I don't like you and probably never will.
FK: The feeling's mutual.
IK: But maybe if you promise to stop destroying my place, I'll come visit your place sometime.
FK: As long as you promise not to ruin my kingdom when you do visit.
IK: Always gotta negotiate, huh, kid?
FK: Heh, it's what I do, old man. I promise to keep my end.
IK: And I may promise to keep mine.
*The two kings reluctantly shake hands literally for a second…*
FK: Ahh! We should have used gloves.
IK: (whimpers) Now you think about that.
Finn: Ha Ha! Yeah, I forgot, ice and fire don't mix.
FK: No duh, genius. Oh yeah, speaking of that O Icy One, how did you get out of my cage?
IK: I made a quick ice shield, jumped out and waited for the right time to strike. By the way, your cage was fizzling from being around so much snow, so it became fairly easy for me and Jake to escape. You picked a fight in the wrong side of town, partner.
FK: (Sarcastically) Thanks for the reminder. I'll never forget it.
IK: Oh, I know. (laughs)
FK: (sighs) Anyway, Good luck with these guys foiling your princess plans, Ice King.
IK: Good luck not going crazy in your kingdom, friend.
Jake: Take it easy, man. Maybe me and Finn will visit, too.
FK: If you do, don't just walk in. Call first. Or in your case, Finn, just scream real loud.
Finn: No problem. It was fun battling you, Fire King. (does a short bow)
*With a quick nod and smile, The Fire King flies off to his kingdom, where he may forever dwell…*
Finn: I'll be honest, Jake. That guy can be awesome when he wants to.
Jake: Yeah, he may be a little different, but he could be a cool friend.
IK: Not as cool as me though, right guys?
F&J: WAY cooler than you.
*At this, the two heroes laugh while The Ice King loses it and chases them out of his kingdom. They head on to their house, laughing all the way there.*