Evil Fic:
Marisa gets a nice, say, stick through the lung. Not fatal, but a really good reminder of her mortality, especially when it ends up with Alice treating her...
Then Yukari decides to have an idea at the worst possible time, and triggers a Border of Tsundere and Yandere on poor doll queen, causing Alice to develop the bright idea of 'fixing' Marisa perfectly.
Ensuing BAD END as Marisa is tied down and modified in a rather horribly descriptive fashion into a sentient doll, each organ sliced out one by one until she is nothing more than a nice grade of plastic... And Alice, in full Yandere mode, decides to
eat each one, in full view of Marisa, so that she can have that next bit of the magician's essence to help make the Doll more powerful.
That image'll give me nightmares. Please, someone, make it reality so I can scream at a Touhou fic for once. :V
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Sillier(ish)... May as well reveal what my plans were for the Code Geass/Touhou crossover.
Summary of events shown: Lelouch (as of Episode 14 of R2) walks up to a shrine, ending up walking through what is coincidentally the Hakurei gate, and landing his ass in Gensokyo. A dealing with Remilia lets him pull off a mass subversion of fate, allowing him a chance to go back in time and save Euphemia.
Unfortunately, this also had the side effect of unleashing the Scarlet Sisters on Area 11 - only a lucky reveal that
one weapon that the Black Knights had would weaken them, and the fortuitous arrival of Reimu Hakurei, saved the lives of most of the million murdered in the original timeline.
Meeting up with Reimu, Lelouch managed to end up Geassing Yukari into service with the Black Knights...
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Big fact reveal: Geass would only work on Youkai
if they wanted it to. Remilia would show this by getting Flandre to let her memories be modified by Emperor Charles L. Brittania, before the same being done to herself, with the intent of erasing any friendships with people like Reimu so that she could inflict the kind of mayhem she had long desired - and get revenge on the kid dumb enough to outwit her.
Meanwhile(?), Lelouch would find things going all too similarly - successfully pinning the blame for the unleashment of the vampires on the Empire and starting a (much better organized) attempt to capture Area 11. He also would find unusual allies in the Scarlet Devil Mansion team - turns out Sakuya's a hunter who was trying to keep Remilia benign, hoping this would break the century-based cycle her line had been stuck in. That failed, she quickly (if sadly) talks Patchouli, Koakuma, and Meiling into joining her on taking Remilia down.
Sadly, he chooses to bring Yukari instead of C.C. with him when he is forced to rescue his sister - and things really go wrong when, upon confronting Suzaku and being overpowered, Lelouch begs Yukari for help - only to be coldly told, "You told me I serve the Black Knights. That's different than serving you, dear. I can set up another Zero." She then leaves with Kallen, leaving Lelouche to his devices...
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I wasn't sure if I would write the middle (between the end of the first season and the start of R2 - one year's time) or not, but the important thing was, the fight eventually settled down - no captures, no surrender by either side, but lines were relatively stabilized, splitting Japan into the Special Administrative Zone, the Developed Area, and the now-named Neo-Gensokyo regions among much of Japan. Every so often, one of the Knights of Round (now including both Scarlet Sisters, working under the names Remily Li Brittania and Flandre vi Brittania) would attempt to break the line, only to be held off one way or another... And it doesn't hurt that everyone was surprised by the introduction of a second Zero - who would turn out to be Eirin Yagokoro.
Lelouch, sent back to the Academy, ends up with Sakuya taking the place of Sayoko, and (for pure lulz value) Patchouli as a mysterious new instructor at Ashford Academy.
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R2's progression would be severely screwed up by the new introductions - while we can ignore the finer details, three massive planned changes (spoiler'd):
Spoiler:
* Shirley Fenette's life is saved - right as Rolo starts slicing into the girl, and sadly right after the wounds would be fatal, his time-stopping Geass gets one-upped by actual Time Stopping. Sakuya, having developed some caring for possibly the closest person to Lelouch in the interceding year, proceeds to beat the everliving crap out of Lelouch's fake brother. Maybe one fourth of the fight actually has them trading time-stops and tricks. The resulting different injuries give Shirley more time - before she manges to get into her last words, Koakuma shows up, rapidly figuring out that the wounds are fatal, but making Shirley an offer...
* Yep, Shirley takes it, becoming a little devil so that she could have more time. From here on, Lelouch has the support... But can't escape the resulting nagging feeling that he could have saved her from this entirely.
* Suzaku's launching of FLEIYA gets aimed, rather than in an attempt to scare of Kallen, right at Yukari. Having a hint of forewarning, Yukari quickly tries to gap the bomb into empty space, but ends up hit head-on by the blast. Tens of millions of people are saved, but for two shikigami, that's a VERY small consolation...
* Lelouch, armed with better knowledge than before, manages to face his father to greater success, this time inspired not by having nothing to lose, but by having friends who deserve better...
* ... It's just too bad he forgot about Remilia, isn't it? She promptly moves her way into the throne, promising even more oppression and rapidly forcing pretty much everyone together against her. It doesn't help that Flandre, serving as a diplomat, tricks the majority of the Black Knights into turning - only Kallen ends up choosing to stay loyal to Lelouch.
* The ensuing battles end up pretty spot-for-spot - Remilia herself proves an incredible military leader, but without heroes like Cornelia or Suzaku at her side, is lacking a critical edge. It doesn't help that certain people aren't willing to kill certain others....
* Neither side ends up at a lead, until poor Nina, ignored for the entire fanfic because she's not a fun character to write, finally completes the FLEIYA canceller... Unfortunately, about the only person that could use it would be Yukari. Say, shouldn't Chen and Ran have lost their powers a while back, given that Yukari was the ultimate source of them?
* Yeah, she's alive... and Lelouche immediately panics. The wording of his Geass technically puts Yukari at the command of Remilia, as she casually explains... Fortunately, she has no particular interest in the girl ruling the world, so she's just going to ignore it, and pose an intellectual challenge to Lelouch. The FLEIYA canceller, as built this time, can only carry one person. That one person was expected to be Yukari. Yukari, however, has blessed "her favorite Earthing", such that it will work for that one person. A massive logical mindgame ensues between the Gap Queen and Lelouch, until he finally figures out that it is...
* ... Cecile. Yukari liked the Wasabi Sandwich incident's results, apparently.
* ... Nope, she was lying. It's C.C. Time for green hair big butt to go save the world, Yukari promptly teases.
* Epic final fight here, ending in Sakuya managing to knife Remilia through the heart. "I'm sorry, my lady. Perhaps next time?" "Have the tea ready." Cold finish.
Yeah, I'm a total uncreative hack. :V