Since Kieran has been kind enough to open up the Grail Works setting into a shared universe and others have spoken of crossovers using the concept which they can't write themselves, I figured I'd go ahead and set up a separate thread for discussion of fic ideas using the concept.
First thing's first:
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Project Summary:
As originally conceived, Grail Works is a shared setting designed to be used as a plot device by any writer on the Beast's Lair - similar to "The Challenge." And, oddly enough, Grail Works is also based on an idea I stole . . . Er, that I got from the same author, alternatively known as Kestral, Metroanime, and one or two other aliases. And like him, I got some help with developing the idea - he had Skysaber, I have Inugami.
The basic idea here was to give everybody a plot device for crossovers, AUs (alternate versions of themselves looking for help, for example), and maybe an overarching series they could contribute to. As a result, a lot of this is played lightheartedly and for fun - so if the character descriptions don't quite match what you think they ought to, don't worry: they're not really meant to. As it has a couple of author characters already, more are permitted - but preferably only one per person, and ask permission, if you want to use them - please and thank you.
Now, as the history of things stand in this setting, it's fairly simple. In an alternate timeline (call it the "Ilya Route"), Shirou actually got his wish, and formed this troubleshooting agency. They operate out of a subdimension contained within Avalon, overlapping their own world through the Emiya home. So they can leave the bubble to go shopping, etc., but are also self-contained, when necessary. Avalon does require periodic charges of prana to keep functioning, but they have enough mages and magical creatures to go around that it's not a huge problem. The Grail Works crew (from the Fate side) are Shirou, Saber, Rin, Sakura, Rider, and Ilya. They've recently added the Tohno household (Shiki, Akiha, the maids and Ren) to their ranks, along with the Tohno manor property. Through the magic of dimensional overlap, both manors are contained within Avalon, but do not appear to have moved within the physical world - so walking across the lawn could take them to either house, or outside to Fuyuki or Misaki, depending on their desire.
(*Note: In the original version, Shiki was romantically paired with Arcueid - this was later changed to Sacchin, to reflect their shared setting as being "the universe of the underdogs." At present, since Inugami seems to be stuck, I'll leave the actual choice up to anyone who wants to write about that group.)
Typically, a client shows up (from somewhere), and one or more of them attempts to help. They prefer using their own abiltiies first (and frequently scavenge other realities for useful items to help them do so, so things like lightsabers, or enchanted armour, or other odds and ends litter their equipment room). However, if something requires a really massive change, they have access to the Holy Grail for a wish - but they need to charge it up first. Therefore, they spend a lot of time hunting for (usually magical) objects or sources that can be drained into the Grail in lieu of the souls of six Epic Spirits. The adventure of these hunts could be stories in themselves, for those who'd like to try.
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Current Personnel Status:
Shirou is pretty much himself, at least at the "end of the Fate route" level of competence, maybe more. He's usually the one off dealing with clients' problems. In the original setting, he's romantically uninvolved with any of the girls, much to their frustration - but a later version had this classed as an "Ilya ending."
Saber is a dragon, much to her dismay. A well-meaning client tried to pay the Works back by reincarnating Saber to break her contract as a Servant, and somehow managed the hundred-to-one odds of reincarnating her as this (though something in her karma likely played a factor, as well). She now regards the client as a half-rate, dim-witted excuse for a hedge wizard, much to said individual's dismay. While perfectly capable of appearing human, she's more than a little upset with him at the loss of her humanity, and the draconic urges she now has to deal with. For example, she's started accumulating a treasure hoard - although in her case, her preferred "treasure" seems to be plushies.
Rin is on board with this whole thing as a way to refine her craft - and God knows, Shirou would be hopeless without her.
Sakura is as she would be at the end of Heaven's Feel's Good Ending, sustaining a contract with Rider to drain off the ridiculous amounts of prana she's got left over. She doesn't do much adventuring herself - she's more about seeing that everyone's taken care of when they come back.
Rider is Sakura's Servant - period. If Sakura wants her to do it, she'll do it. Right now, Sakura's behind this whole idea, so she's all for it, and will help where she can. Besides, they come across some of the neatest vehicles and creatures! She's secretly hoping to eventually get her hands on one of those speeder bikes from the last Star Wars movie - they look fast.
Ilya is presently functioning as the "master computer" of the complex. She opens Doors to other dimensions (for clients or operatives), monitors them, and protects operatives from being overwritten by the local reality laws - otherwise, to use an example, Arcueid might find herself interpreted as a traditional vampire, rather than a True Ancestor. Within the complex, Ilya is a physical being - but outside of Avalon's reach, she could only appear in a wraithlike form. Her "body" (the Grail) is housed within the most secure portion of the Works' Inventory Room (their equipment storage space, and Saber's current lair). She is constantly seeking a way to detach herself from the Grail, and inhabit a body again, so she looks at methods of soul transference. Reincarnation doesn't really appeal, after seeing what happened to Saber . . .
Her biggest worry is that one of the other girls will seduce Shirou before she manages to accomplish it. Frequently, if a mission involves dealing with pretty girls, she'll send someone else, and work to keep him out of it.
The Tsukihime cast was discussed above. Story ideas Inugami and I batted around when Arc was the main girl was reincarnating her as something outlandish, like a demon character from the Disgaea series, but with Sacchin, we thought about making her Rin or Sakura's apprentice, and Garm her familiar. Nothing major set for the rest, other than Ren - Garm is her "big brother" (see below).
Garm is Inugami's author-created character, a dog familiar that seeks to protect Ren, with power over shadows and flame. He's distrustful of magi in general, owing to bad experiences, but willing to ask for help in finding his sister, whom he lost track of several centuries ago. PM Inugami for details and permission if you want to use him.
Kyou Sonozaki is a guy in a girl's body... how's that possible? Well, a random schmuck from one world (the author behind Kyou's creation, AKA Xamusel) accidentally made contact with a being calling itself Deus (short for its full name, Asmodeus) and made a deal with him. The deal went along the lines of "Give me a piece of your very self, and I'll give you a power beyond your comprehension," wherein the schmuck gave him a number of character sheets based around a tabletop RPG adaptation of an original character from his Gundam fanfic writings... the adaptation being for a modded d20-style crossover game (which consists of Star Wars Saga Edition, 13th Age, Pathfinder, Dungeons and Dragons 3-5e [not 3.5e, that means from 3e to 5e], and various anime). Thus far, Kyou is trying to find a way out of being a girl full-time, or even part-time, thus (mostly) taking on missions that pay a guaranteed wish of any sort, even if they might not work.
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Mission Log (and Assigned Personnel):
(Grail) Works in Progress: Origin Stories - Kieran
Melancholy of One (Shiki, Arcueid) - Pureauthor
Magical Amber vs. the Mushroom Kingdom (Kohaku, Hisui, Ayako, Taiga) - Pureauthor [MISSION COMPLETE]
The World Which Sings for Salvation (Sakura, Rider, Will) - Lyric Rome [DISCONTINUED]
Journey Into... School? (Akiha, Arcueid, Satsuki Ayako) - MWkillkenny84
Inhuman Resources (Rin, McNab) - Vigilantia [Incomplete]
Dead in the Water - Draconic
FUTURE ASSIGNMENTS (ASSIGNED PERSONNEL):
Untitled Demon Souls/Vagrant Story Mission (Saber, Shirou, Ashley) - Hymn of Ragnarok
Kyou's Dilemma: Book 1 "Coordinating Trouble" (a Cosmic Era crossover) (Kyou, Sakura, Rider)
Kyou's Dilemma: Book 2 "Forcing Your Way" (a Star Wars crossover) (Kyou, Shirou)
Kyou's Dilemma: Book 3 "A Newtype of Crazy" (a Universal Century/13th Age crossover) (Kyou, Rin, Saber)
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A NOTE FROM COMARTEMIS: Please PM me if changes to the setting or characters or new stories require updates to any of these lists so I can keep them useful and up-to-date.
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Secondly, two ideas have already been brought up; a cross with Fire Emblem 6 and a cross with Madoka Magica.
For the Fire Emblem cross I think the ideal insertion point would be for Saber to play the role of the Tactician since she's the only one in the group with military and command experience. Since she's horribly OP for the setting even without Excalibur and Avalon, I think the challenge would be for Saber to pull off a No Casualties run (without the benefit of a reset button), but I'm sure we can throw more complications than that at her, like Ninian and Nils recognizing her as a fellow dragon even with the polymorph spell in place.
Madoka Magica is the harder one since the universe itself is trying to screw over the heroes and there's no easy solution to the network of problems presented. Get Arcueid or someone to kill all the Incubators and the universe dies, and killing the witches doesn't stop the Incubators trying to recruit Madoka. I do like the idea of the crossover, since Ilya (if QB could contact her somehow, maybe via a Door or something) is young enough to be a potential target but also savvy enough to rip her recruitment agent a new one when negotiations happen.
Thoughts, anyone?