*sighs*
Alright, I've got a confession to make.
I stole Firnagzen's notes in an alternate timeline where Kennedy wasn't assassinated which almost resulted in World War Three, yes, again.
Unless you want spoilers, this is the place where you should stop reading.
Okay? Okay.
So, Walpurgisnacht has a hidden counter that raises up with each Meguca we recruit for the final confrontation, raising again for each of them depending on how high their Social Link is. The higher the counter is, the more phases she unlocks.
That means that she becomes more powerful the more effective our assembled force is, up to and including Proto Kriemhild Gretchen.
So, in the final phase, once Walpurgisnacht starts turning upside down to destroy the city ( and possibly Japan ), we get to fight the real Walpurgisnacht on the gear at her base, which, need I remind you, is tilting. The real Walpurgisnacht is an assembly of a hundred plus Guca-Shades who sit on the Greek-style forum around the amphitheater which shows the shit Gubdam Walpurgisnacht is wreaking in real time, but once we crush the party, they start screaming at Sabrina specifically for breaking the fourth wall, copying their shtick and Mary Suing their performance. Then the amphitheater becomes an arena and our Meguca Force has to fight wave after wave of Guca-Shades, while one of them is ineffectually screaming at the rest and calling for moderators to stop this shit. Then, after the last wave, Walpurgisnacht finally stops and starts disintegrating, only to stop doing that too after a few seconds. The world greys out as if Homura used her powers, but she obviously didn't, but before we figure out anything else, that one Guca-Shade who was trying to stop the others appears in front of us and starts explaining everything.
Turns out, Homura's Wish was unsurprisingly vastly beyond her Potential, so the actual thing she could hope for was a poorly made Madoka-simulacrum somewhere between a person and a familiar, who pretended not to know who Homura was so she could meet her again for the first time, only to sooner or later realize that she was a fake and Witch out.
But, Walpurgisnacht is actually an acausal being approaching something resembling a godhood after all the Witches they omnomnomed. Sometimes, they attack cities to devour Witches and watch stuff blow up and allow Meguca defenders to "defeat" them, only to return a few decades later.
So, one of the collective heard Homura's Wish and decided to help her out, at first mostly because she was bored and wanted something interesting to happen. She linked Homura's Potential to Walpurgisnacht, which allowed her to become another acausal entity with the power to "look behind the curtain" and "rewrite the script". After explaining that, she flat out asks Homura why else she thought her Shield had suspiciously similar-looking gears and then starts screaming at her for being so bad at this that she actually started rooting for her dumb ass. And yes, she actually wants us to win, because the gig became stale and dumb after a few hundred times they did it, which wasn't helped by Homura failing against them so many times, when the prerequisite for defeating them was literally to recruit anyone else beside herself and fight together.
So, she started noticing that the one girl Homura is trying to save becomes more and more powerful with each timeline, and quickly figures out the rest of the script that if it doesn't stop, she'll become a goddess that creates heaven for Magical Girls, which sounds pretty swell.
And then she accuses Sabrina of ruining it with her fix everything shit and calls her a derivative work that doesn't mesh with the tone of the series. After calming down a little, she says that this isn't the end, because even though the Fluffy Wolf Madoka no longer exists in this universe, the echo of her still does. And the UKG definitely exists, because she's the collection of all despair stored together in one being, which everything gravitates towards sooner or later, and Madoka not becoming a goddess doesn't really stop that.
So yeah, UKG saw this shit, and now she's interested and wants to play, good luck with that.
( if we ask her whether she remembers who she was before at any time, she gets upset, says "it's unimportant, you tart" and then ignores us for the rest of the conversation, only listening to questions from Homura, Sayaka, Kyouko and Mami from then on )
Then she disappears, but the time doesn't resume. Instead, a giant pillar of Grief tears through the sky and falls on Walpurgisnacht who is still frozen in the mid-dissolving. The flood of Grief doesn't stop and starts drowning everything around us, and we have only just enough concentration to create a barrier around us to protect us and the rest of the Meguca Force.
Once it finally stops, we drop the Grief Dome and look around and shit's fucked. It looks exactly like the ruined Earth on which UKG was trapped inside Homura's Shield, only instead of a lifeless wasteland it's all alive and wants to kill us. The air is poison, the earth is writhing, and there are giant tentacles in the sky.
More and more Grief Shades appear around us, forming out from the earth itself, looking kinda like Walpurgisnacht Shades, only there are many, many more, a tiny fraction of the all Megucas who ever fell into despair.
If at any moment our Soul Gem fills up more than halfway with Grief, black feathers start falling from the sky, and the Grief around us starts pulsing. You know, because it wasn't fun enough before that.
And then they momentarily stop attacking, the sky clears from the south a litttle and Madokami appears from the sky through the crack. She starts Befriending everything around us with the Giant Bow of Friendship, only we figure out after a few moments that something's wrong. Madokami isn't winning, exactly. In fact, she looks a little bleak, like a faded out photo reel and grows dimmer with every second. She drops beside us, and continues shooting, but at one moment looks aside and smiles sadly at us, then Homura.
So, from that moment on, everything depends on how far along we helped Homura with her problems. If she's not well off enough. She cracks under the smile, curls on herself and, well, nothing good happens. If she is, she straightens up, walks toward her and presents her with her Soul Gem. Madokami looks shocked. Mami looks shocked. We look shocked. Madokami stretches out her trembling hand to Homura's Souk Gem, and before we can figure out what the fuck it even means ( is she sacrificing herself or something? What the fuck? ), the Soul Gem flares up and Madokami starts glowing noticeably brighter. Then Sayaka smiles and does the same, then Mami, then we, then everyone around us, and we can't quite figure out how many Gucas are around us, only that there are more than we started with. Madokami smiles radiantly, then with a look of determination stretches out her bow, aims at the sky, and fires.
Fade out, epilogue reels.
...Okay, now that I presented you with the most meta animesque final boss battle I could think of, can we please stop speculating about it for awhile? We already know that we need allies and that we need to help out our friends, so how about we focus on that instead of the meta commentary on a battle that's still two weeks away with an opponent of power levels literally being "YES, except if fighting Madokami".
We can discuss it once we start actual preparations, in five years or so.
