I thought it might be fun to look at some minor issues in Proven Guilty.
Harry hits the Winter Wellspring with Summer Fire which causes every Winter Fae on the border with Summer to rush back to Arctis Tor to try to kill Harry. After getting back to Chicago Harry discovers that this was what Lily hoped would happen. Harry figured out that Lily and Maeve were working together because when time got slowed down around Arctis Tor, this allowed Summer forces on the border with Winter to leave their defenses and go attack the Red Court and only Maeve had the ability to mess with time and how it flowed around Arctis Tor. (OK Mab or Mother Winter could do the same thing but Lily wasn't talking to either of them.)
So here's mystery #1: Did Harry have to specifically hit the Winter Well Spring to make this plan pay off? Because if he did it seems like a real low probability move by Lily. Harry could have fried Eldest Fetch without ever touching Winter's Well and how could Lily even predict Harry would have to get to the top of Arctis Tor in order to rescue Molly? Theoretically, the battle could have taken place downstairs or in some room within the castle or on the stairs leading to the top. Perhaps Maeve might have suggested where Harry would have to go to find Eldest Fetch and Molly.
Even so, what if Harry hadn't hit the Well with Summer Fire and instead used Summer Fire to knock down a wall or parapet that was an integral part of the castle. Would this have had the same effect on the Winter Fae at Summer's border? I can't prove this but I have a feeling it would have been the same or near enough to make no difference in the overall result. The way Jim has written about Mab's palace; though admittedly that's very little, suggests Arctid Tor is almost alive, and perhaps even sentient. The way the castle reacted to blood being spilled on its floor is suggestive of the first and in Cold Days Harry mentions some lights and or shifting colors within the walls that he decided were probably unsafe to stare at for too long. This suggests Artic Tor is more than another pretty Faerie Ice Castle. There may be a specific psychic connection between Arctis Tor and all of Winter. Someone could stand outside and throw rocks or even Hellfire at it and it wouldn't cause a reaction but an attack using Summer Fire or perhaps any specific Summer magic would cause all of Winter to come back to defend their Capitol. So that's my answer to my own question.
Minor mystery #2: Was Maeve surprised that Lily's plan worked? Maeve didn't think very highly of Lily so I wouldn't be surprised if she expected Lily's plan to fail. If this was the case that would mean Maeve wasn't happy she had to slow time and allow Summer to attack the Red Court, but she had no choice if she wanted to continue to deceive Lily.
Minor mystery #3: Was Maeve surprised that Harry survived his encounter with Eldest Fetch? I'm guessing Maeve knew about Eldest Fetch because during the final confrontation with the Scarecrow Harry realizes he's dealing with a fetch, but one that has been granted extra power. This suggests Nemesis involvement, though it doesn't absolutely prove it, but what else explains this? If Maeve expected Harry to die than except for continuing to reinforce Lily's trust in her, Maeve didn't have a very good day. She had to help Lily attack the Red Court which, even if it wasn't a full ally was at least a useful asset, and the annoying wizard survived another violent encounter that should have killed him.
Do you have any different explanations or other questions about unsolved Proven Guilty mysteries that; as far as you know, haven't been discussed yet?