A short while ago, Agatha stumbled across the Mirror and accidentally activated it, starting the Infinite Agathas plot. Meanwhile, though, the device rewrote reality slightly, giving her a new family and a new life as Maria. This is how she starts the game. Only Dingbot Prime, who witnessed the transformation, knows what is going on, and is faithfulling following Maria just as it would Agatha.
Does Agatha remember this, or is it an amnesia plot? --Darker Justin: Amnesia plot, albeit with a substantial number of hints. The theory is that this is a first-hour plot, to keep Agatha offstage at the beginning and complicate her life while giving the player something to do, but expecting that she and her coterie will unravel it by mid-game. Besides, it gives me something to do with Maria, a character I'm fond of.
Another possibility that might add meaning to the title of the game, and spice to the "Who's the real Agatha?" confusion: The original Agatha's mind was put into a construct or clank of some sort, while her body is (in stasis, asleep, in a dimensional pocket, ?). As such, she wouldn't smell like a Heterodyne to the Jaegers (though it now occurs to me that the same is true with the reality-rewriting version above). --Darker Justin: Yaas -- physically, she isn't a Heterodyne at the start. And the title specifically refers to Sarah...
Maxim found Maria in the woods, and knows that she smells like Agatha. He isn't quite sure what's going on, but is following her, somewhat suspicious. Krosp's sense of smell isn't quite as precisely attuned to Agatha as the Jagers' are, but he knows that there is something bothering him about her; if he specifically focuses on her smell, he should realize that she smells exactly the same as Agatha.
Characters In Game: Agatha Dingbot Prime Krosp Maxim
All Characters: Agatha Dingbot Prime Krosp Maria Maxim
The way this was originally designed, Maria had the Headaches Special Disability -- each time she tried to think too hard, she got a headache, came to a GM, and would get one of Agatha's Special Abilities. Eventually, she would finish that up and get the Real Agatha character sheet, splitting back into Maria (now an NPC) and Agatha.
In practice, we wound up finding opportunities to foist the abilities on her. Whenever she seemed to be in a situation that might be relevant to one of Agatha's Special Abilities, we would give it to her. We gave her the less-informative abilities first: we started with Master Musician in both cases, which worked well, and gradually worked up to the more Spark-relevant ones. When giving her the abilities, we tried to give her descriptions of memories relevant to those abilities -- for instance, we gave her Intimidation when she had been interacting with Gil, and described one of her arguments with him on board Castle Wulfenbach.