Shannon and Kannon
Think about what you wrote there. No, I mean really think about it.
The obvious conclusion to draw would be that Shanon and Kanon aren't human, and play by similar rules to all the other supernatural entities that appear on the board. And they never take advantage of the fact because they still consider themselves furniture.
Evatrice
I'm pretty sure that was supposed to be symbolism or something. Since in Ange's mind, Eva is the embodiment of pure evil, she;s just blaming her for everything that goes wrong in her life. Also, as soon as one of her crazy evil aunts dies, another immediately comes after her? Possession doesn't even seem that far off. Eva just hadn't had enough of torturing her yet, so she came back to finish up. ...No, that's not true at all, but it's probably what Ange was thinking at the time.
Probably, yeah. It's hard to tell exactly what happened at the end there with Agne was truth and what was in her mind. Especially considering that she's listed as having died at that point in time.
Ergh... I thought you'd get this by now... Virgilia the piece =/= Virgilia in the Metaworld. There's the game board, right? That's where all the murders take place. And then there's that higher plane where the red truth vs. blue truth battles happen. The fandom has dubbed that to be the Metaworld. Beatrice in the Metaworld controls the pieces on the game board. That's not their real personality, that's just Beato showing a bit of flair for the dramatic.
I get the difference between the different worlds, but it never seemed to me like Beato can control all the pieces. And supernatural entities (Beato, Ronove, etc.) seem to be able to shift between the game board and the tea room at will so I considered the Virgilia that helped Battler in the tea room and the one who helped Beato at the end of game three and throughout game 4 to be the same. If the Virgilia on the gameboard (or at least the one on the board after her big fight with Beato) is a replica of whatever controlled by Beato, that explains the personality switch (though not why she hasn't returned to the tea room since late in game 3).
Battler's Parents
Come on now, if someone suddenly told you that the person you thought was your mother - took care of you your whole life, and died not too long ago - was not actually related to you at all, wouldn't you be pretty upset? Really, you left the family for six years because your father betrayed her... and she actually wasn't involved anyway. The grandparents you lived with all that time weren't even your grandparents. I can't blame him for freaking out there...
To a point, yeah. But I'd think the first thing he'd try to do was regain some sense of self by at least trying the red truth for his father.
The Number of People
Aye. She only ever said no more than 18 and that there was no 19th person. And... what was the exact red on this one? Wasn't it "no more than 17?" You're gonna love Book 6.
Er... Please don't tell me there's really less than 17 people. I mean, I can see Kinzo's presence being faked but I don't think that'd work with any other character.
Beato
There are a lot of different Beatrices at this point. Remember that player Beatrice and Piece Beatrice are completely different entities. The one that appears on the game board is more like the "idea" of Beatrice, the witch that lives in the forest. But she's just a piece. The one that Battler deals with in the Metaworld is the real Beatrice, the one with the actual personality. Gonna give you a spoiler: Lambda's bluffing. How the hell would she know? She's not involved in Beato's personal life; she's just trying to trip Battler up so the game will go on longer.
Going off of the way things were handled in previous games, it seemed more to me like Beato could just jump back and forth between the board and the tea room and play both roles, the exception being her human self who appeared in games 2 and 4. Sounds like I'll need to adjust my reasoning on how that works... As for Lambda, I realize she could be lying there (she was talking to Bern though, not Battler), but I'm not completely discounting her claim either.
First game, first twilight. Six corpses in the gardening shed.
The killer poisoned or shot the six and either had a key to the shed or stole one.
First game, second twilight. Two corpses are close together in a closed room protected by a chain.
I'm tempted to stay someone killed them, locked the room, and hid under the bed like Battler suggested. But I don't remember whether or not everyone's wherabouts were accounted for at that point. If they were, I'll need a different theory.
First game, fourth twilight. The old Head from the closed room study, confined in a scorching furnace.
Kinzo was killed early on when everyone's whereabouts were in question. He could have been lured out of his room or the killer may have taken the key. After that, killing him and sticking him in the boiler wouldn't be that hard.
First game, fifth twilight. The last moments of the sacrificed boy with a stake in his chest.
A trap or accident makes the most sense but here Lambda's red truth poses a problem. According to her, he was murdered yet everyone's whereabouts seem to be accounted for unless someone faked their own death earlier, which Beato denied. I'd need to review the red truths for this one.
First game, sixth, seventh, and eighth twilights. Three corpses lying in a closed room of the singing girl.
Did that room fall under Beato's defacto locked room definition? Well, all four people in that room were declared, in red, not to have been the killer. I'm going to say that Maria was working with the killer. She opened the door, the killer did his thing, then Maria locked the door again after he left.
Going off all that, if there's only one killer for the first game, he/she is one of the 17, and faked deaths and body doubles aren't used, I'd probably finger...Jessica. I mean, the only people who survived are the four cousins. Battler is out and Maria was declared not to have killed the last three. That leaves George and Jessica and going off personality, knowledge of the mansion, and ability to impersonate Beatrice, that leaves only Jessica.
Second game, first twilight. Six with their stomachs split in the closed room chapel.
Once again, poison or a gun explains the killings easily enough. As for how they got in the chapel... What were the red truths related to the chapel and its key?
Second game, second twilight. The corpses of the two who are close are not close.
A gun and a master key can easily solve this. Beato never said the servants always had control of their respective keys. And that's assuming a servent wasn't the killer.
Second game, fourth, fifth, and sixth twilights. In Natsuhi's closed room, none are left alive.
Same as above.
Second game, seventh and eighth twilights. The two sliced to death by the red-eyed phantom.
The question here isn't how they were killed but who did it. I believe red truth stated that Kanon was dead and they wouldn't have mistaken someone disguised as Kanon. That would mean Kanon being the killer was either a magic illusion or a lie concocted by Genji to protect the real killer.
If Kinzo wasn't declared as being dead, he'd be the number one suspect here. Rosa is suspicious as well, though she has an allibi for some of the murders. That leaves...Genji?
Third game, first twilight. Six corpses connected by the linked closed rooms.
I'm pretty sure Battler solved this when he said that the killer simply made sure to be the first person to examine one of the bodies and pretended to find the master key.
Third game, second twilight. The corpses of mother and child lay together in the rose garden.
Eva did it, with Hideyoshi covering for her.
Third game, fourth, fifth, and sixth twilights. Three corpses lying in the mansion.
Eva still works, though I do have trouble seeing her killer George.
Third game, seventh and eighth twilights. The corpses of husband and wife lay exposed under the arbor.
Really, Eva as the killer solves all of these pretty easily. All except for Nanjo's killing... Did Lambda shoot down Battler's last theory for that one, about one person who they thought was dead killed Nanjo and then died?
Fourth game, first twilight. A massacring storm sweeps through the dining hall.
Someone walks in with a shot gun. Poison darts or, more likely, a knock out gas grenade could explain how the others got to the cell. Though I wouldn't completely put it past Kinzo to design a dining hall with lots of crazy pitfalls.
Fourth game, second twilight. The two young ones face their trials and pass away together.
The only weird thing here is Jessica's phone call. If you discount what she said while on the phone, neither murder poses any real problems. An alternate theory is that Jessica fought George (as part of their test) and was fatally wounded in the battle. She then escaped to her room and made the call but the killer showed up soon after to bash her head in.
Fourth game, fourth, fifth, sixth, seventh, and eighth twilights. None of the runaways are left alive.
Once again, it's not a matter of how they were killed but who did it...
The main question here is who was able to kill everyone else. Allibis are the issue here. Perhaps the killer gased everyone in the dining room, locked himself in the cell, pretended to be a victem, and implanted the Kinzo massacre story in everyone's heads when they work up. Alternately, it could have been someone who was in the guest house but not being watched by the others.
Fourth game, ninth twilight. And none shall be left alive.
I'd need to review the red truth related to this one. There really isn't much to work with though.
And the final question. Who is Beatrice?
As in who is she as a person (Kinzo's mistress, illigitimate daughter, etc.)? Or which of the 17 people is filling the role of Beatrice? If it's the later, my top pick go to Jessica (she looks the most like Beatrice and I can pin some murders on her) though I could build partial cases for Eva, Rosa, Kumasawa, and Ghoda.