Bill had gone back to his previous red and black color scheme.
He had also sprouted several extra arms, and the different sections of his pyramid had split into two sets of gaping mouths, with ogre-like yellow fangs and grotesque black tongues jutting from them; the latter of which writhed hungrily in the air as he burst into the clearing.
Incongruously, his monstrous form still included his little top hat and bow tie. Ford wondered if maybe they were just a natural part of his old "friend's" physical form, or if he'd just forgotten about them in his wrath.
Either way, somehow their presence made Bill a little more horrifying.
The spirit warrior barely had time to brace themselves before the demon charged at them, snarling with fury, more like a crazed animal than his normal-well, not exactly dignified self by a long shot, but he had definitely been more restrained with his craziness in the past.
Now, however, his attack knocked them off their feet, and they barely managed to dodge away from the swipe of one of his hands and slam one of their boots right in his eye.
Bill shrieked, and another hand lashed out at them blindly; before it could make contact, the warrior's beard wrapped around his wrist and yanked him off balance, sending him crashing into the trees.
Fiddleford whooped triumphantly, and did a little jig in the middle of his spot in the circle.
"Take THAT, ya ugly geometric disaster!"
The warrior got back on their feet, just in time for Bill to come lunging at them, two hands at once curving themselves into long, jagged claws. They raised the sword just in time to block the attack, but were shoved back, with their boots digging deep furrows into the earth in a frantic effort to regain purchase.
Just as they were about to smash into the front of the Mystery Shack, the warrior let go of the sword's handle with one hand, which covered itself with a fresh layer of ice, and sent a fierce left jab right into Bill's face.
Pieces of shattered teeth pinged off their armor, and the demon let out a high shriek of pain and rage.
The warrior took a staggered step back, and lifted their sword to chest height, before driving it right toward his eye.
Just before the tip of the blade could make contact, though, a glowing yellow light sprang up, which it clanged off.
Undeterred, the warrior adjusted their grip and tried again.
In the Mystery Shack, ten people concentrated all their life's thoughts and experiences (up to and including what they'd learned from movies and video games) into fighting the triangular behemoth.
Pacifica focused on everything she'd learned from fencing, even though the heavy claymore-like sword the warrior was using was far different from the graceful épée she favored in combat.
Stan and Ford used every dirty trick in the book (and even a few they came up with on the spot), such as at one point gaining a little extra ground by bringing one of their heavy boots right down on Bill's exposed foot or jabbing him in the eye with two of their six fingers.
Soos pretended that he was gripping the world's biggest game controller, and used it to make the figure duck and weave to evade the attacks from Bill's terrible claws and bursts of magic.
Wendy channeled her strength and anger into their fists as bursts of cold, merciless ice.
Gideon, showing surprising strength for his size and personality, created colorful versions of the star of telepathy and used them to block the demon's spells, or send them flying back at him. That'd teach the isosceles monster ta make him do cute dances when he didn't wanna!
Fiddleford wished fervently that he had his banjo, or somethang else ta hit the bas-(he remembered there were children present)...ketcase with! Instead he made do with the mighty big sword they were holdin'. A couple times he had the warrior hold it in their beard ta let the fists do their work, while all the while their eyes darted back and forth in their glasses, lookin' fer an opening.
Robbie, without really knowing how he was doing it, used the power of the stitched heart to keep everyone's energy flowing smoothly so none of them would weaken too soon, and they could all gain from the others. He'd never exactly been the heart of a group before, leaving that job to those who were better at caring about other people's feelings and needs, but now he was the one forced to carry that burden.
Mabel urged all the fervent hope for the future she possessed, and even her childish enthusiasm and willfulness, into the strength of the shooting star. Magic flowed down the length of the sword, slashing and ripping through Bill's defenses and hacking at him in an attempt to find a weak spot, to put an end to this monster who had hurt her family once and for all, so their world could have peace and happiness again.
Dipper gave all of them the strength and sturdiness of the pine tree, making sure they would not be knocked off their feet too easily and that they could take a hit and come back swinging.
None of them seemed to notice how exhausted they were becoming, or the long streaks of white starting to develop in some of their hair.
A little part of Bill, a part that he never wanted to admit existed, knew that even if he somehow won this fight against the Zodiac, he had basically lost.
His rule was crumbling to pieces around him.
He was trapped in this stupid town, and as much as he hated to admit it the dumb baby was right-the continued rip in this dimension, without a bigger world to sustain it, would soon enough undo the fabric of reality beyond even what he was capable of enjoying.
He didn't even have his henchmaniacs anymore; they'd all gone running off like cowards or been cut up by this big prophesied freak.
No matter what the end result was here, he didn't have a chance of coming out on top.
Unfortunately, among the many things that Bill Cipher was not (human, mortal, a decent person, as funny as he thought he was, etc.), the phrase "a graceful loser" must be included on the list.
If he was going down...he would happily take everyone else with him.
And as he and the Zodiac kaiju battled their way back and forth, fighting and blocking hits and smashing a lot of trees into kindling in the process...he wondered if the humans realized the true implications of joining together to complete this thing, and how they could perfectly suit his desires if this fight went on for long enough.
See, the thing about creating a "mystic energy circuit" was that it couldn't be sustained indefinitely, at least not if you were using non-magical mortals. Sure, the Zodiac's power was still nothing to sneeze at, especially when created by people who had done and been through so much; but eventually-maybe it was even happening now-the spell would start to take its toll.
And since Bill was immortal, and a being of pure energy...well.
All he had to do was wait them out.
They couldn't keep this up forever.
The first one to notice that all was not well was, oddly enough, Robbie.
He looked over at Wendy to see how she was holding up-and let out an alarmed sound.
She frowned at him in confusion, after wiping her forehead on her sleeve. "What?"
"Uh-Wendy-" he stammered awkwardly- "your hair-"
"What about it?" She twisted her head, trying to figure out what was wrong. She looked back at Robbie questioningly-and then she saw that one of his bangs had developed a distinct white streak, standing out from the black like a skunk stripe.
Worriedly she looked at the others-and sure enough, they all appeared to be developing it too. And realized the same thing must have happened to her.
Quickly everyone else began to realize the same thing.
Pacifica let out an alarmed cry, and nearly let go of Mabel's hand in order to check her own locks-but remembered just in time why that was a bad idea. She let out a frustrated whimper, and muttered something about how if they survived, she was going to have to buy a fortune in beauty products.
"Great Uncle Ford!" Mabel called worriedly, "What's happening to us?!"
Ford grimaced. "It's the spell! It's starting to-dig into the deepest levels of energy we've got! But we can't stop now! We have to focus!"
"Easy for you to say!" Robbie protested. "Your hair's already gray!"
...But he shut up at the withering glare the old man gave him.
For a moment the warrior's attention was taken away from Bill; it was all he needed to wrap his magic around them, lifting them into the air, and then hurl them away.
Then his monstrous form lunged over to the Mystery Shack, and pounded a fist on the dome that sprang up.
"KNOCK KNOCK!" he screeched gleefully, his voice far more unhinged than any of them had ever heard it before. "GETTING TIRED IN THERE?! WOW, IT'D BE AN AWFUL SHAME IF WE HADDA CUT OUR FIGHT SO SOON-"
He whirled around just in time to catch the warrior rushing up behind him, and lunged, carrying a ball of fire in one giant fist that smashed right into their chest.
In the circle, everyone gasped at the sudden burning pain, which nearly sent them to their knees, as their giant avatar was knocked to one side. Their form flickered in and out of shape for a moment as several grips nearly loosened at once, before managing to restore themselves.
They managed, thanks to Ford's catlike reflexes, not to completely lose form and land in a decent stance, and retaliated with a swipe from their sword that Bill barely managed to block in time, but it took them a few seconds to get to their feet and return to fighting the demon blow for blow.
"Everyone stay calm!" Ford ordered, putting all the command at his disposal into his voice. "We can do this-we have to do this! We're not going to let Bill win!"
He tried not to think about how he was trying to encourage a group of literal children to keep fighting a giant eldritch abomination, and hoped instead that the spell would somehow distribute a little of his strength and courage to them.
Somehow, though, this next round of battle was even worse than the one before.
Bill attacked even more mercilessly, now that he knew that the spirit warrior could be sort of hurt, and it was all they could do to keep him at bay.
Despite this, every time they got knocked down, the warrior got back up again.
And again.
And again.
Before long the once-pristine gray armor had torn open in places, revealing translucent skin beneath. There was no blood leaking from the wounds, but they glimmered in the dull red lighting, and as stoic as the warrior's face continued to be, you could tell that exhaustion was settling in.
Bill's different sets of mouths, and his black and yellow eye, were creased in smug triumph as he once again beat them back against the trees.
"FACE IT, KIDS!" he cackled-in a voice that carried, if you were looking for it, a hint of odd relief. "YOU'RE ALL OUT OF YOUR LEAGUE HERE! YOU MIGHT AS WELL JUST GIVE UP AND ACCEPT DEFEAT NOW, BEFORE THIS THING TAKES WHAT'S LEFT OF YOU AND-"
"HEY! LOOK OVER HERE, UGLY!"
The demon slowly turned the top part of its body to see who had dared to address it.
He saw a group of small, puny humans standing out in the open, waving their arms and grinning at him.
Over at the house, several more of them had just finished dragging the statues of their fellow townspeople onto the porch, and to comparative safety.
Grenda, who was one of the ones in the clearing, waved and yelled again.
"YEAH, I'M TALKING TO YOU, YA BIG JERK!"
"Your three-sidedness offends me!" Candy joined in. "It goes against nature!"
"AND YOU DRESS LIKE THE MONOPOLY MAN! BOO!"
"Git'em, git'em!" Tyler chanted, pumping his fists in the air.
"PUNCH HIM IN HIS STUPID EYE!" Manly Dan roared.
In the split second in which Bill was caught off guard by the blatant insolence of these tiny meat sacks who dared to insult him, trying to decide if they were enough of an annoyance for him to obliterate off the bat or just ignore them until a later period when he could torment them to his heart's content-he made the mistake of letting himself get distracted.
It was the last mistake he would ever make.
Seconds later, he felt a sharp, ripping pain, and the eye at the front of his body got a good look at the tip of his sword being driven through the area right under it.
The warrior didn't stop there.
They twisted the sword to the side, and pulled, tearing it straight through Bill's side until it was free again, and began to chop and hack at him with reckless abandon, even though there was no need.
Slowly but surely, and with increasing speed, the particles of Bill's body were breaking down into tiny golden flakes, which were being kind of absorbed into the blade.
The demon screeched, and tried to leap away, but one of his arms disintegrated, so he fell to the ground with an unceremonious thud.
The warrior planted their boot on top of him, and raised the sword over their head. The once-expressionless eyes glittered with collective hatred for this creature and everything he had done to them.
And Bill-he just started laughing.
A feeble, but still defiant, laugh, as his form changed, as best it was capable now, back to his familiar yellow, cartoonish shape.
And then he began to sing with what remained of his voice.
"We'll...meet again...don't know where...don't know when…"
The blade came swooping down to meet him.
"But I know we'll meet again, some sunny-"
The final blow met its mark-
-and Bill Cipher was gone.
As the last remnants of his form disappeared, mostly becoming absorbed into the spirit warrior's blade, the world around them changed.
The fleeing henchmaniacs were yanked unceremoniously into the air, and sucked back up towards the rift, along with many other monsters, bubbles of chaos-all the horrors Bill had brought here from the Nightmare Realm.
The angry red light was rapidly replaced by warm blue skies, the green of pine trees, the golden glow of the summer sun overhead.
The waterfall, which had become a fountain of upward-flowing blood, returned to its natural state.
The sentient water tower ceased its rampaging and returned to its normal spot.
Gompers the goat sank back to his normal size, and was only a little confused that the pine tree he had been munching on was now taller than he was.
In her house, Abuelita Ramirez woke up as she fell to the floor with a thud, now that she was no longer a comfortable red armchair, and decided that now that she had her limbs back, she would go and see where her grandson had gone off to.
The stone statues of Robbie's parents, Mr. Poolcheck, and the others returned to normal, and looked around in confusion as they tried to understand what had happened.
In the clearing, the Zodiac warrior slowly got down on one knee, resting their hands on their sword, and bowed their head, like a knight showing fealty to a king...before slowly dissipating into strands of light which flowed back towards the Mystery Shack.
And in the kitchen, ten people collapsed to the floor and didn't get up.
...If it makes you feel better, this isn't quite the end yet. No need to get in a tizzy at me.
Hopefully this met with everyone's expectations; I felt like giving them a quick win would be too easy.
