This excellent AU is not mine! I just write in it. It was created by Steeldragondown and coffee-elemental. Also read Reverseworld Time with Finn and Jake by Steeldragondown! It's not necessary to understand these stories, though.

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Monster Castle's basement had surprisingly good acoustics. Simon began to incorporate a lot more bass into the rhythm he was playing, as much out of scientific curiosity as a desire to make interesting music.

Marceline stopped singing along with Gunter's keyboard and called "Drum solo!"

"Oh, oh, uh..." Simon fumbled with the drumsticks, and managed something pretty passable.

Marceline was so good. Sometimes Simon was proud of what he could do with the drums, but he wasn't nearly as good as Marceline and her singing. Of course, he was a bit younger than her. He wasn't sure by how much, but she was definitely older than she seemed. That was the thing with vampires. They stopped aging when they were bitten. Marceline was going to be in her late teens until the day she died.

He dropped down to a simpler snare rhythm, and said "Thanks for inviting us to jam with you, Marceline."

"No problem," replied Marceline. She strummed a few chords on her bass. "Sometimes it's just nice to zone out and play, you know?"

Simon had not been zoning out, but he didn't want to admit it. "Uh, yeah!" He tried some syncopation, tried to keep it going without concentrating, missed a beat, and winced. He wasn't ready for the zone-out level of musical accomplishment just yet.

Marceline began to sing again, but quickly stopped. "Uh-oh. While I was zoning out just now, I had... a vision."

"Wow!" said Simon and Gunter in unison.

A number of questions came to Simon about the kind of vision, which sense was most prominent, whether the Cosmic Owl was present, and whether she'd got a vision because she was a vampire, because of her demon blood, or from something else entirely. Before he could figure out how to ask them without being called a dork, Marceline said "Sorry guys. I gotta go check on something."

"Ooh!" said Gunter, turning his keyboard off and leaning over in interest. "What is it? Is it your new bass player? I told you you should have let her take her metamorphasis leave."

"Is it about... your vision?" said Simon. He wished he got visions more often. He only ever got them from outside influences. And then he usually had to bash the outside influences with nunchucks because they were evil. It sucked.

Maybe that was where Marceline had got the visions? From something evil he needed to bash with nunchucks?

Marceline hesitated, then said "Tell you what. How about you two come with me? You were probably just gonna follow me anyway."

"Yeah, we probably were," said Gunter, putting his instrument away in its case.

"Don't tell her that!" said Simon. He was right, though. He was getting pretty good at keeping out of sight. "We'd love to go with you to check on your vision, Marceline!"

"Okay, just..." Marceline floated over to one of the cardboard boxes lining the walls, and began tossing things out. "Ugh, where is it? Aha!" She pulled out a couple of circlets and tossed them to Simon and Gunter. "Put these on. They'll protect you from mind control."

Simon did so. "Cool!" What could they possibly be going to check on that required this much preparation? It sounded like an adventure in the making.

Gunter tilted his head. "Simon. Tell me the truth. Does this thing make me look girly?"

"Aren't you a girl?" said Simon. He could never tell.

Gunter shrugged.

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The three of them took a submersible under the biggest tar lake in the Monster Kingdom. "Now, maybe you've heard of this guy," Marceline began.

"It's Peppermint Butler!" said Gunter immediately.

"Bonnibel's creepy manservant?" said Marceline. "No! It's-"

"Donny?" said Gunter. "Muscle Princess? Tree Trunks?"

"Gunter, why would Tree Trunks be hanging out in a tar lake in the Monster Kingdom?" said Marceline. "There aren't even any apples down here."

Gunter shrugged, and started to suggest something else.

Simon grabbed Gunter's beak and held it closed. "Gunter, quit messing around." He was getting really curious, and Gunter would keep talking all day if he got a chance.

"No, the guy we're checking on is way more dangerous and evil than Tree Trunks," said Marceline, curling her hands into claws for emphasis. "He had a lair out past Iceberg Lake, where he tried to suck up all the planet's life!" She hissed.

Simon gasped. He had heard of that guy. "The Lich! It's here?" He peered into the tar, but all he could see was blackness.

"The what?" said Gunter, inappropriately unconcerned.

"The Lich!" repeated Simon. He couldn't believe Gunter had never heard of it. It was kind of the greatest evil in Uuu. "Some say it always existed. Some say it was created as a byproduct of the Great Mushroom War. But everyone agrees on one thing. It is a killer! All it cares about is destroying all life in Uuu - in the world!" He checked that the circlet was still on his head. Now he understood why Marceline had given them to them. "It's like, mad dangerous!" he finished.

"What does he look like?" said Gunter, still with much less gravitas than the situation demanded. He pressed his flippers against the front window. "I bet he's just made of muscles, like, his entire body is one big pec, and with just one arm he could lift an entire battilion of-"

"Gunter, this is serious!" said Simon. He thought he could whispering now. He wasn't a coward. At least, he thought he wasn't. But his mind was the second-best weapon he had, and the Lich was not taking it away from him.

A horned skeleton with flesh still clinging to his bones appeared out of the murk, and Simon jerked back. He'd the Lich before, in books, but it didn't measure up to the real thing. It was so big. Despite being completely still, it seemed to stare right at him.

Marceline breathed a sigh of relief. "Good, he's still here," she said. "I was really worried for a second there. He's encased in the toughest, stickiest tar in the kingdom, and we all have protection from his mind control, so it's-"

Abruptly the submersible pitched forwards, right into the Lich.

"What-" began Simon. He checked his circlet again.

Gunter pointed. "Look! The controls!"

Simon looked. "The waving snail! It must have come in with us!" He lunged for the snail, but it was too late. The Lich became a black mist and flowed through the diving bell, on its way to the surface.

Marceline put her face in her hands and groaned. "Great. I guess I shouldn't ask you two to do something about the Lich, but-"

"Are you implying that we couldn't stand up to pastyskull up there?" said Gunter, indicating the empty mass of tar in front of them. "Come on, we're heroes!"

"Yeah!" Simon agreed. "We'll stop the Lich, or die trying!" And they weren't going to die. Even against the Lich. He hoped.

"Those are your only two options," said Marceline, which didn't make Simon feel any more confident. "Come on. I'll show you where we keep the secret weapon."

That sounded good.

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The secret weapon turned out to be the gauntlet of the legendary Billy, the hero who'd defeated the Lich in the first place.

"You mean to say that Billy defeated both the Lich King and the Lich?" said Gunter, as Simon tried out the gauntlet. "He's just so... He's amazing, that's what he is."

Marceline made kissy noises, and Simon laughed.

Gunter blushed, and said "Oh, come on. It's just a little... little penguin crush." He twiddled his flippers.

Billy was pretty great, Simon had to admit. But he hadn't defeated two liches. Just the one. "The Lich is the Lich King," he explained, glancing at Marceline, who was looking through her pack. "Remember that interdimensional exchange from last decade?" The delegates made a pretty good argument for why their Lich King was much more of a King than Uuu's Lich King. Simon didn't understand why there was only one being in the multiverse who could be called that, but the committee had apparently been on the delegates' side.

"Oh, you mean when you were still wearing nappies?" said Gunter.

"They were not nappies!" He'd only had to wear them at night. He'd had a bed wetting problem. But he wasn't about to admit that in front of Marceline.

"Simon," said Marceline suddenly. "I, uh, wanted you to have this. It's... It's kind of chilly in the Lich's lair. You know."

Simon, who was still thinking about the Lich King, started to say that it wasn't like it was like it was in the Ice Kingdom. Then he saw what he was offering him. It was a sweater, red with a black collar. It felt kind of scratchy. "Marceline, did you... make this?" Marceline was not much of a knitter.

Marceline looked away and said "Just take it, okay? Be glad I didn't stitch spider fangs into the inside."

Simon was pretty glad for that. He pulled it on. "Thanks a lot, Marcy! Are you gonna come with?"

Marceline sighed. "I wish I could, but... I better stay here and reassure my subjects that the Lich is not going to blow up the planet again."

Simon opened the door. "Okay, we better hurry- again?"

"Never mind," said Marceline. "Just... come back safe, okay?" She leaned down and kissed Simon on the cheek.

"Oi, where's my kiss?" said Gunter. Simon pushed him out the door.

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"All I'm saying is-" Gunter gasped for air as they ran towards Iceberg Lake. "All I'm saying is- You don't even like like Marceline. She- She's like your big sister. Except a vampire!"

"What do you mean, like like?" said Simon, who was much more concerned about catching up to the Lich than whatever Gunter was complaining about.

"You know, like like" said Gunter. He waggled his flippers around. "Like like like."

Simon was beginning to get the picture. "Gunter..."

"Like like like lik- Oof!" Gunter bumped into someone big and blue.

"Finn-Ice?" said Simon. He put his hand to the pocket where he kept his nunchucks, glad to get off the topic of like liking Marceline. He'd never thought about that before, and it made his skin crawl.

Prince Finn-Ice picked himself up and said "Hey! Watch where you're going!"

Gunter shook his flipper. "Oh yeah? Why don't you watch where you're going? And also take a bath!"

Finn-Ice stared at them blankly and stroked his beard. "Man, what was I going to say to you two? Uh..."

Simon kept his hand on his nunchucks, but he said "Look, we don't have time for this. We have to stop the Lich. Do even know what the Lich is?" He doubted it. For a wizard, Finn-Ice was pretty dumb.

"Well... maybe I don't have time for you!" Finn-Ice yelled, and flew into the sky.

Gunter looked up after him. "Weird. Wonder what he wanted."

"Who cares?" said Simon. "Come on, we have to go after the Lich!"

Gunter started running again, but he said "Ugh, I am exhausted. Tell you what, we'll camp here, and we can go after the Lich King in the morning."

Simon slapped him. "No! Come on!" What would it take for Gunter to understand that this wasn't a game? This wasn't some lowly skeleton monster. The Lich would kill everyone on Earth if they let it.

"All right, all right," said Gunter.

They sped up.

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Marceline strummed her guitar, sighing. As usual, she'd just made things worse. Not in setting the Lich free. Self-fulfilling prophecies were tricky, and she'd long ago stopped beating herself up when she got caught up in one.

No, it was the royal speech that she'd skronked up. She guessed she probably shouldn't have listed all the ways that the Lich wasn't going to destroy the world - fire, flood, explosion, putting the planet in a bag of holding and throwing it into the sun... - or at least, she shouldn't have gone into detail. But how else were they supposed to know what they didn't have to worry about?

Simon and Gunter would be fine. They were always fine. Even against an incarnation of pure destruction that had terrorised the world for centuries and taken a true hero to-

"Maybe I better go after them," she said aloud. "It's not like I'm doing any good here." She floated out of her castle, over the Monster Kingdom, which was a lot brighter than usual with all the arson and rioting going on, and towards Iceberg Lake. After a second's thought, she touched down and shifted to wolf form. That was faster. She didn't know why she didn't do this more often.

She located the very distinct scent of penguin, and followed it through the grasslands. She was making good time. A few more minutes and she'd catch-

A bolt of ice hit her from above, freezing her back legs.

Oh. That was why she didn't use this form much.

Finn-Ice came down from the sky. "You're a big puppy, aren't you?"

Marceline tried to free her back legs, but they were so cold she could barely move them. And if she couldn't move her legs, she couldn't shift back. "I'm not a puppy, you psycho, I'm a wolf! And I'm not a wolf, I'm a vampire!" What was he, blind? She didn't even look like a real wolf.

"A talking puppy?" said Finn-Ice, squinting at her. "That... That's totally math!" He seemed to come to a decision. "Come on, puppy! This will show Simon and Gunter! I don't need their approval! The approval was in me the whole time!" He tapped his chest.

"What?" said Marceline.

Finn-Ice picked her up and headed for the lake, where Gunter was swimming after the Lich, with Simon riding on his back. Simon was using Billy's gauntlet as a motorboat engine, but it didn't look like he could get a clear shot yet.

"Hey!" called Finn-Ice. "Hey, you guys! Look! I caught a dog all on my own!"

They ignored him. Marceline was kind of proud. Finn Ice was not the issue now. The Lich was the issue. She'd made the right decision in entrusting the safety of all life on Earth to these two. Probably. Responsibility wasn't her strong suit. It was easily the most boring part of being a queen.

The moment that Simon got in range of the Lich was the was the exact moment Finn-Ice chose to drop down and hover right in front of them. "Pay attention to me, guys! Would you just look at this dog!"

Simon lowered the gauntlet. "Marceline?"

"Look at this dog!" Finn-Ice exploded, and pitched Marceline into the water. "Oops. Just... Just stay there, puppy..."

"Marceline!" said Simon. He leaned over the side. "Stay still, I'll blast you loose with the gauntlet."

"N-" Marceline went under for a second. The ice on her back legs floated so well that it was hard to keep her head above the surface. "No!" she repeated, spitting out water. "The Lich, Simon! Stop the Lich!"

"Oh!" Simon glanced ahead. "He's nearly there! Gunter, hurry up!"

"I'm trying!" said Gunter.

Simon put the gauntlet back in the water, and they sped away.

Marceline was almost glad when Finn-Ice picked her up again. The boys needed to focus on stopping the Lich, not whatever trouble she'd got herself into. She'd be fine as soon as she got rid of the ice. For now, she amused herself with fantasies of what she'd do to that weirdo when he let her go.

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"It went down there!" said Simon, pointing at what looked the entrance to an old... what was it called? A subway, that was it.

"I know, I saw it!" said Gunter. He slid down the stairs, with Simon following close behind.

The subway was quiet. It looked like nobody had been there in years, maybe centuries. There was definitely no Lich. It was pretty hard to miss.

"You know, out of all the scary holes we've been in, this is definitely the second or third most... ancient," whispered Gunter. He tapped a subway car lightly, and it crumbled. "I... I meant to do that."

Simon found it more or less like any other creepy hole of indescribable evil. "Holes are holes," he whispered back.

"What's that me- uh-oh."

The ground began to rumble, and a group of skeletons in pre-Mushroom war garb pulled themselves out of the dirt.

"Hey skeletons, did you see where-" Simon began, and jumped out of the way as the skeleton swung at him. "I guess they have poo brain."

"Low level mooks always have poo brain," said Gunter, who had one clone of himself holding a skeleton down while two others pummeled it. "I've always wondered about that."

"Well - eat gauntlet!" Simon fired at the skeletons, with very satisfying results.

They rushed down a few more levels of the subway, to a hole in the ground that emanated disturbing whispers. where the Lich was drinking from a well of green, glowing liquid.

Simon gasped. Green and glowing was the universal symbol of radioactivity! It must have been left over from the Great Mushroom War. "Gunter, I think the Lich needs radioactive liquid to survive! Do you think it was created by the Mushroom War? Is that why it wasn't mentioned in the historical record before then?" Historical records from the centuries after the war were patchy, but the Lich appeared in them again and again.

"I dunno," said Gunter.

The Lich looked up, and Simon remembered where they were. "Eat gauntlet also, Lich!" He fired a beam of energy, which the Lich dodged.

"He's too fast!" said Simon. "I need to get in closer!"

Gunter grew to a huge size. "Whatever you say!" He grabbed Simon and flung him down at the Lich.

"Hey Lich, I got som-"

The Lich grabbed the gauntlet. The gauntlet shattered.

Before Simon could process what had happened, the ground rushed up at him and he landed on his face and slid into a wall.

The whispering got louder.

Simon felt his head. There were no lumps, but something was missing. He glanced around, and saw the mind protecting circlet, half buried in the dirt three feet away. "No!"

"Simon..."

Simon looked at the Lich. He couldn't look away. He could barely turn his head at all. He thought he could hear Gunter saying something, and... was that Marceline? When did she get there?

"Simon, walk into the well..."

Simon tried to stop himself from walking forwards, without much success. The vibrant green of the Lich's well did look kind of inviting. It looked very inviting, compared to the vague blackness of the rest of reality. He could barely make out anything other than the Lich, and that inviting green well.

"Simon... Come here, Simon... Aren't you cold, Simon?"

He was... He felt... He did not feel cold. "I'm wearing a sweater!" Simon blurted. He pulled at it. Somehow, just thinking about the sweater cleared his head.

He didn't get much chance to enjoy his lucidity, because the Lich snarled "You are a joke to me!" and blasted him with radioactive green fire.

Simon screamed, until he noticed he wasn't being burned alive. In fact it didn't hurt at all. He looked down. Was it the sweater...? The sweater Marceline had made him? Maybe... Yes, that was it! He got it now!

He pulled off the sweater, rolled it into a tube, and jumped at the Lich. "Lich! Queen Marceline made me this sweater! Gunter was right, I do think of her as a big sister! And she thinks of me as a little brother!" He hoped. "That's why she made me this sweater! This sweater is imbued with the power of... the power of caring for someone intensely in a familial sort of way! That's what is going to defeat you, Lich!" As he spoke, he whipped the Lich with the sweater, making it stumble into a wall. "While you were trying to mind control me, I thought I heard Marceline's voice! That's what this sweater does! It reminds you of your loved ones!"

He whipped one more time, as hard as he could, and the Lich's head cracked and imploded. The Lich's lair came back into focus, and Simon jumped down.

"That was a really corny speech, you know," said Marceline.

Simon dropped the sweater and whirled around. "Marceline?!"

Finn-Ice was holding Marceline above the well of radioactive goop. She was still in her wolf form, and still trapped in ice.

"You heard me because I was right here, you dork," Marceline added, but she was smiling.

"I tried to tell you, but you were off in your own little world," said Gunter, waving a flipper.

Simon felt his cheeks grow hot. He was never going to live this down, ever.

But at least he'd have a chance to try, because he'd defeated the Lich, and life would go on. He'd actually managed to defeat the most evil and terrible being in Uuu. The worst was over. "Finn-Ice, let her go!" he said. "She's not even a dog!"

Finn Ice turned to look at Marceline, and wrinkled his forehead. "Then why does she look like a dog, nerd-boy?" he demanded, releasing Marceline and waving his hands around.

Marceline dropped right into the well. The ice burned off, and she reverted back to her humanoid form as she vanished beneath the surface.

Finn Ice looked at Simon and Gunter, then at the well, then at Simon and Gunter again. "Uh... Oops?"