Murder By The Book - Ender's Game

I doubt that Mirdini actually knows what the pie does (or that he's gonna make it online before deadline, so you listen up sonnie.) Mirdini is making an educated guess that it is one of any of the following:

a) It does nothing
b) It kills you if you eat it
c) It kills the recipient if you throw it at them
d) It gives somebody information about your role or alignment (e.g. it's a copping, or it tells the Piemaker what your abilities are) if you eat it
e) It does the same, but to the person who gets pied
f) It leaves a persistent effect that may prove positive or negative

Things we know about the pie:
1) It wasn't intended for you, if Garu is correct about their oneshot Superwatchering, because it was given to Person A, redirection antics happened (obligatory: Simple setup my ass), and it ended up at your doorstep.
2) We don't know who, if anyone, received a pie on N1. The pie could be oneshot. The pie could be sent every night and Cyber got it N1. The pie could have been sent to one of the players who haven't been active since N1 and they haven't mentioned pie receipt.

My personal guess is that the pie performs an investigative action on the eater. If you are town, it's almost certainly to town's benefit for you to eat that pie, because with the current information handy we have to assume it's the only pie we get.