Basically taken from TVTroupes and expanded upon.
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We all know her, and most of us love her. But now that time has passed, and many people are thinking more of our new magician Byakuren, and our new Crow Tengu Hatate.
Does this mean Miss Margatroid has been forgotten?
No, but let's take a look back on her Lore, and by the time most people read and comment or discuss this topic.
But moving on, Alice Margatroid made her first appearance as, Alice, in Mystic Square, being the second boss to appear in the main story as a boss, and then appear as the Extra Boss. (The first being Rika)
In Mystic Square: Alice took the "Grimoire of Alice" and used it in the extra boss fight. Only to be defeated shortly after.
Now, what happened to her book after that? By the common knowledge rule of Touhou, I'm not allowed to spoil that, for it was told in the ending. But when we see Alice again, approximately a year after the last events of the PC-98 era, we see her all grown up, with the book, and out for revenge.
One concern some fans might notice: "How did she grow up so quickly?" "Is the book she using the same?" "What happened to everyone in the PC-98 Era, and why only Alice (And Yuka) made it into the windows series?"
Well, the answers are clear, simple, and probably implied. Alice is still out for vengeance. Out to fight Marisa and Reimu, to get back at them for her defeat in TH5.
Another person who did a WMG on Alice, claims that Shinki warped Alice into another dimension to get her away from danger. Taking her away from the harsh world of the PC-98 era, to the safe lands of the Windows Series, where the spellcard rule is in use. This way, Alice can live a more simple life, without worrying about death... as much. The guess also says that Alice was sent incredibly far back in time, to make up for the fact that she's all grown up, in what seems like one year.
As claimed in PMiSS, Youkais all age slower. This includes Magicians. Patchouli is about 100 years old, Byakuren around 1000, and Alice is unknown. Why is that? We saw her in PC-98, her age should be known. They didn't even give her the "About X years old" business they usually do for many other characters, like Cirno. (But then again, many other characters suffer from unknown ages)
Now how did Alice Margatroid age so quickly? Is the WMG explained above true? or is there another possibility.
This my Wild Guess.
Alice Margatroid is a Doll.I have many evidence to support my claim.
Like explained above, PC-98 and windows are about 1 (one) year away from each other. What happened, is that this doll, called Alice Margatroid, is a reflection of what Alice could have been if she grew up, but since she opened the Grimoire, that won't happen.
And Shinki's power is unknown, so the whole "Warping Alice to another Dimension" is possible, however unlikely, since her power has something to do with Sara, Luize, Yuki, Mai and Yumeko, since it was established, that everyone (And retconned out, excluding Alice) was created by Shinki. So unless she has an incredibly vague power like Yukari's Manipulation of Boundaries, it's safe to assume that Shinki's power is to give life.
That said, it would be unlikely that Shinki can warp Alice. The only way that this Larger, grown up Alice is possible, is that it's actually just a doll.
And as said in Alice's physical description in PMiSS
"She has blond hair and pale skin, and looks very much like a doll herself."
Looking like a doll would be very difficult to do without make up. And since this is Gensokyo, I would assume the only person who would have access to make up would be Marisa and her Mushrooms, or Yukari.
however, it's also states that "She's the type of magician that was originally human and became one through training."
Why is that? Could it be I'm wrong just because this is true? No, because here is my next wild guess.
There are two Alices.One who is a doll, and the other who is a the real, PC-98 Alice. The Alice we see today is actually just a doll controlled by the Alice from the PC-98 Era. So to make things more simple, Alice from the Windows series will be refered to as Margatroid, and Alice from the PC-98 era, will be named, Alice.
Moving on, "
Margatroid's dolls appear to be able to act and talk independently."
Which means, that Alice is also capable of doing this.
In PMiSS, it's also claimed that Margatroid has the ability to make dolls control other dolls. If Margatroid can do this, then Alice can as well. Where the Margatroid dolled is controlled to Alice's will, she can make it do as she pleases.
Now why doesn't Margatroid ever use her Grimoire of Alice? This is because it's not the real Grimoire. It's a false replica to make Margatroid look like Alice. Where Alice has the real Grimoire, using it to control Margatroid.
With this, we answer the question about Miss Margatroid
Quick Aging [She didn't age, she is a constructed Doll]
How she knows Reimu but she doesn't know her [Reimu wouldn't know someone who is all grown up. I'm sure it's hard to recognize them. However, since Margatroid isn't exactly Alice, of course someone would be strange that someone you never met came up to you and wanted you dead.]
How Margatroid can move around if she is a doll [Thanks to many claims in PMiSS]
Why Margatroid never uses her book after PC-98 [She can't, because it isn't real. Alice has the real one.]
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And that's the wild guess, thought I'd share it along with this:
http://i39.tinypic.com/b3ln5e.jpg<Tengukami> Please keep images under 640x480, and less than 150 KB. Thanks!