AN:

Thanks muchly for all the warm welcoming backs, first and foremost! These sort of inklings come in drips and dribbles, and every bit of outside support is that much more motivation to continue. Sam, Neverthrive, XYZ, and everyone else, your praises feed my fires, thank you. Also, Kazuo, that's a wonderful coincidence, glad I could make it happen!

In this chapter… Well, I won't spoil it for you, but I'll give you a hint, in that one of the things I've learned between when I started writing fiction and now is that stories thrive on conflict; if things go too easy for too long, they start to get boring reallllll quick. So hopefully y'all won't hate me for throwing a 'wrench in the works' (title drop!). Anyways, here the plot deepens! Enjoy!

Chapter 7: A Wrench in the Works

The door swung inward, ice built up around its frame tinkling as it was disturbed. The room clearly hadn't been entered in quite some time, as the door stuck and jammed itself several times, forcing Marceline to throw it past the blockages.

"Geez," she muttered, hands crossed over her belly as she drifted through the open door, kicking at the frost coating the floor. "Would it kill the guy to clean up once and a while? Or at least send someone to do it? I mean, he's made of molten metal. Wouldn't be very hard, would it?"

"Yeah, I guess not," Finn replied. "But that's his forgemaster biz, so whatevs."

Passing through the doorway, they came out into a large, circular chamber, with three other doors identical to the one they had come through lining the perimeter. In the center of the room stood a tall pedestal, atop which was an ornate cylindrical casket, covered in gold and silver detailings, like tongues of flame leaping from the bottom of the casket towards the top. The whole thing was encased in a massive ice formation, rock solid.

Marceline let out a breath she didn't know she'd been holding. "This is it bright eyes," she said. "We grab the bass, then we go give Thoros the what-for, and then we blow this taco stand."

"Hmph," Finn slapped one fist into his open palm. "I say we give him a thrashing on the way out. You know, just to keep things fair."

"Yeah, I hear ya," the vamp said in agreement, casting a small, wistful smile back at her mortal buddy. "Thoros would probably kill him with one blow, but he's still chomping at the bit for a few licks on your behalf," she considered. "Selfless, altruistic, adorable mortal. But I'd rather not push our luck Finn. One brush with final death is enough for one day."

"Mh," Finn said, not happy with it but nodding just the same. "So, bass is all frozen up. How do we get at it?"

"Just gimme a little swinging room, bright eyes, I'll take care of it. Go… Keep watch, or something."

Finn nodded, turning about and walking off as Marceline began to shift to her more monstrous form. "Yeah, definitely not something I wanna spend a lot of time looking at," he mused, looking about the room. "You picked a real winner this time around. Immortal blood sucking undead overlord… Or overlady. Something. Real winner though. Jake is gonna flip when I tell him."

As Finn shoved off to 'keep watch' as Marceline had directed, something came immediately to mind, words that she had said to him years ago. 'Finn, you do not want to go down that road with me!' It was as though a bubble had suddenly popped up in his brainpan. "Oh yeah, that's right," he thought glumly. "Marceline plus lovey-dovey leads directly to demonic tentacle monster. Urgh, Finn, you dumb!" He kicked at some frost lining the blocks of the floor. This was how it always was, with him. Always had been. "You're the hero, that's your role. You fight the good fight, you take the lickings so others don't have to, and you don't complain about it. Because you can take it. And you don't ask for more than you deserve, because that's not how this works; selflessness that's not selfless isn't selfless at all, you know that by now. No special treatment, no expectation. You play the hero's role, you take the hero's lumps, you walk the hero's path."

He growled quietly to himself, kicking the wall of the chamber as he arrived in front of it. "And if that means you walk it alone, well, then so be it. This is the life you chose for yourself. And it's not as though the 'Last Human' could have chosen something different, right? Even if you were a completely peaceful citizen of the Candy Kingdom, you wouldn't be any less alone. At least not romantically. Ya still got Jake, and all your other friends. You're doin' alright, kid."

It was a talk he'd had with himself before, to the point where it played out word for word. Bubblegum. Flame Princess. Now Marceline got added to the dreadfully short list of girls in Ooo he considered anatomically similar enough for a relationship, and the mirror-image list of girls who were definitively out of the picture.

But that wasn't what hero-ing was about. So it was cool. And that's how Finn slept at night.

He eyed Marceline, bat wings spread wide as she began to pound her fists against the ice formation, feet planted, clawed toes digging in for traction. "Well, if that's her true form," he continued in thought, trying to joke himself into optimism. "Maybe I'm better off. Heh." It was a mean thing to think, and part of him felt bad for even thinking it, but it made him feel better about the more personal issue, so he came out with a higher net-happiness. That was something Jake would talk about a lot, 'net-happiness' and 'net-good'¸ and 'net-awesome'. He called 'a way to make tough choices, and feel better about 'em.' Just subtract the bad from the good of each choice, and take whatever has better 'net-value' in the end.

Marcie was still pounding away at that ice. Boy, it was taking a while. Finn looked to one of the room's windows, frosted over but still mostly transparent, sitting recessed in one of the sculpted arches that crisscrossed the chamber's ceiling. "It's nighttime," he said aloud. It was honestly more of a shout, as Finn tried to cut through the crash of Monster-Marcie's fists hitting the ice. "That should make getting back down easier, right?"

"Hm?" Marceline seemed distracted to the extreme. Finn didn't blame her. "Oh yeah. Defs fo' sho', homie."

Finn looked about the room. They'd only been in the chamber for ten or fifteen minutes; judging by how long it had taken them to make the climb, adjusting for some unknowns in how the patrol schedule would change over, they weren't due to be interrupted for at least a half-hour or so. And with the pounding his vamp friend was giving it, the Last Human was fairly certain that the pedestal wasn't trapped. He circled the perimeter of the room, inspecting each of the four doors. They all had falling bars to hold them shut, which Finn dropped in place. Normally he'd want them open to improve line-of-sight, but since the Forgelings patrolled in marching platoons, he was confident he'd be able to hear them coming, and the now-barred doors would hopefully hold any interlopers long enough that he and Marcie could slip out through one of the other doors. At the worst, they'd know someone had been inside, while he and Marcie would have the opportunity to beat a hasty retreat and look for somewhere to hide. All in all, a pretty secure setup.

"So then why are you getting the danger-tingles?" he asked himself. Something was off, in that sinking feeling that Finn had grown to know and respect. There was something he was missing. Eyes cast around at things that he'd already examined; windows, doors, ceiling, the pedestal, but not the floor. The oversight stuck in his mind like the sting of a hornet.

The floor was marked up. Carved into twelfths by thin channels running from the walls to the center, where the bass case stood on the pedestal, encased in ice…

Ice that was in the process of getting smashed. "MARCIE WATCH THE FLOOR!" he shouted, maximum-volume-mode.

Too late. The ice shattered. Marceline had about enough time to look in Finn's direction before the floor dropped out from under her, splitting along its divisions, dropping open, and closing again the moment Marceline was clear. Finn made an agile dive, gluing himself to the wall so that he didn't fall through as well; he'd have a much worse time, he realized, since at the very least Marceline could float herself to a soft landing, wherever the bottom of that drop was. Finn would be paste on the floor unless Marcie caught him.

"Oh glob," the boy hissed in a panic, running his eyes up and down the perforations in the floor and the space that Marceline had inhabited just moments ago. "Oh glob glob glob glob glob. The floor held both of you before. It only sprang the trap when Marcie broke the ice. That means it's at least safe for you to walk on." He scrambled over to the pedestal. The bass case was gone, fallen through with the vampire-beast-person thing who had claimed it. Finn stomped on the floor below him, and though it hadn't given way like it had for Marceline, he was surprised when the floor stomped back at him. "Marcie?" he hollered, stomping again. His voice was tinged with panic; the boy tried to spin it closer towards urgency, not wanting to sound weak. "Is that you down there?"

The call returned, thin, but definitely there. "Y-yeah!" Marceline called back. Down below, hovering up against the floor she had fallen through, Marceline had shifted back to her humanoid form, to make the hovering less strenuous with a lighter frame. "I'm fine, just a little surprised!"

The Last Human let out a sigh of relief, a breath he hadn't been aware he was holding. "Where did it send you?" he called through the stone. Thankfully it wasn't soundproof; Finn attributed that to the breaks in its structure.

"Umm…" the Vampire Queen looked about, trying to get her bearings. "If I had to take a guess, I'd say back into the main staircase!" she told him. Yelling up through the rock made her nervous, the fear of attracting too much attention coming firmly to mind. She considered briefly that, before this little trip that had turned into a long ordeal, she wouldn't have thought to censor her sounds in unfamiliar territory. She hadn't been that prudent before they'd come here. "There's no light though," she continued. "So I guess it must be dark out!"

"The main stairway… Lemme think for a bit!" Finn plopped onto the floor, crossing his legs and scratching his cheek as he ran through what he knew about the situation he was in. He noted immediately that a draft flowed through the cracks in the floor, gentle as it was; probably faint thermals, drifting upwards from the heat down below. However, before Finn could try to spin all the little facts together into a workable idea, he was interrupted by a booming voice that could only belong to one.

"Well then," Thoros thundered, his deep tone thrumming through every inch of his mountain, till it made Finn's molars feel like they were vibrating. "This, I did not expect, though I knew something was still afoot. I suppose my reluctance to pause my work has allowed you the familiarity with these halls to elude me so."

Both Finn and Marceline felt their guts sink with dread, but neither could do anything but listen. "However, it appears that you have moved your pawn to my side of the board," the Forge Titan continued. "You have my instrument, it would seem. As much as I'd love to simply immolate you where you are, I am bound by my word to offer you an alternative. If you can descend into my lair, and melt my face with ludicrous licks, on MY home turf, I will allow you to leave alive, with the instrument, free strings for as long as you live, and another of my creations, which you may commission."

There was a long pause, before finally, the titan concluded; "I await your arrival. Descend directly to the bottom level when you are prepared to begin."

When Thoros was finally finished speaking, it seemed as though his words lay heavy in the air, as though his breath had thickened it till it was harder to breathe. Neither dared to utter a sound, until Marceline finally worked up the nerve to call upwards. "Finn…" she intoned, not trusting herself at all to speak with volume, to the point where she was unsure he had even heard her.

"Y-yo, I'm here." The Last Human was trembling, a fact that he was desperately glad that Marceline couldn't visually observe.

"…What do I do?" Marceline asked. Normally, she flew by instinct, which necessitated less thinking breaks than Finn's analytical, strategic approach, but the immortal mistress of bloodsucking undead was thoroughly convinced that her usual kick-in-the-door-and-take-what-you-came-for style of adventuring would probably bring her long years of undeath to a very final end. She couldn't work up the guts to play that way with Thoros, who'd already almost ended her once that day.

Finn cast his eyes about in frustration. "I…" He had to chew on the next few words to get them out. "…I don't know. I dunno how to make the floor open again, otherwise I'd say wait for me to join you. But Thoros doesn't seem like the type to be kept waiting, and I don't know how long it'll take me."

"If you can't make the floor open again, do you think you could go down one of the secondary stairways, and then cross back into the main one?" Marceline waited on Finn's response with her breath held; the last thing she wanted to do at that moment was face Thoros alone.

Finn thought it over for a moment, but then shook his head with a sigh. "Thoros knows I'm here with you," he began to explain, since Marcie wouldn't have seen his gesture. "He's bound to honor your right to rock his socks off, because you have his bass, but I'm free game. However this contraption works…" He stomped the floor, half in spite of the thing, and half to aim his statement. "…It's separated us. He's probably got Forgelings rushing in droves to come get me, and if I'm moving through one of the secondary stairways, I'm going to run right into them, and that's NOT a good place for a big battle without backup. Sorry Marcie…" His words were soaked in regret, amplified by self-deprecation, for letting them fall into the trap. "…Looks like you're on your own for now."

Marceline swallowed hard. "Alright then," she said back to him. "Looks like there's no way out but forward…" She hefted the case under her arm. Vampiric strength made the thing no heavier to her than it was when she was in her monstrous form, but the difference in size made it relatively bulkier, which was a difficulty in its own right. Careful not to drop it, she held it across both her hands, like a stereotypical groom carrying his bride to the bedroom, and gingerly opened the top.

The instrument within was not what she was expecting, but Marceline wouldn't wish it away for all the gold in Ooo. Thoros' bass was a bass alright, but the bass sat below a standard six-string guitar, both sets of strings with their own fretboards and tuning pegs, but bound to a shared body, one piece of wood. Everything was duplicated; two instruments as one, each with its own knobs, its own output, its own pickups, all of its own equipment, but the top neck had six thinner strings, while the bottom neck had four thicker strings. Guitar-bass combo. The body of it was bare wood, sealed, stained, and polished, leaving the natural grain visible through deep red color, shining flawlessly.

Combo meant options. Options gave Marceline a boost of confidence that she desperately needed if she was going to rock her heart out. Rock ran on confidence. But this was her domain. She was Marceline the Gobdamn Vampire Queen, raddest of the rad, and now she was a trio, instead of a bassist frontwoman with no backing band. "You've got this, baby," she thought to herself, slinging the beast of an instrument over her shoulders. It was heavy, in spite of her supernatural strength. But the weight felt comforting and natural above all else, adding fuel to the fires of her confidence.

"Marceline…" Finn called, still down in his own defeat. "You gonna be okay?"

The greatest rocker in Ooo nodded to herself, tossing her usual rakish grin over her face as she resumed her usual jaunty, devil-may-care tone of voice. "Don't sweat it, babyface," she called back to him. "I'm gonna rock his flobbin' socks off! You catch up when you can, how you can."

Though she couldn't see it, Marcie figured that her confidence would give her new mortal crush some confidence of his own. And she was right. "Go get 'em, Marcie," Finn said to himself, hopping up to his feet and leaving his misgivings and fears on the floor. She'd reminded him that those feelings wouldn't help him anyways.

With that, Marceline the Vampire Queen descended to her latest, greatest gig, while Finn, the Last Human of Ooo, set his own determination on what he did best; helping friends in need.