Possible spoilers if you haven't read the Manga,
My current theory for WHA:
Tartah is injured or under the influence of the brim hats and becomes the next experiment for the silverwood tree. He either accepts to protect Coco or is influenced by Custas' condition.
Easthies escapes on his own to get real answers and find real truths after a crossroads with what he believed was protecting commonfolk from magic. In doing so he delves into an idea of forbidding malpractice of magic not having harsh lines of "this spell is bad and this one is approved".
Qifrey starts turning after finding out Olly knew about everything and used forbidden magic to keep the memory spell from affecting him all this time. Realizing Olly truly stood by his side.
Coco confronts the brim hats and finds Custas and Tartah. Olly has to choose between staying with Qifrey when he has no way to fix him before its too late or to go find the girls. He chooses Coco.
Easthies finds Coco and the brim hats, manic. He tells them both they and Coco are at two sides of a coin that'll never see the otherside. He's unlocked the Tower of Tomes, subduing the sea monster. He's found the answers he wanted. He tells Coco he knows how to separate the silverwood from the host, but will only help her if she says whether she'll share it with the brim hats. Afterall, Sasaran is fused with his pet. It could help them not just in their plans but personally.
Coco decides to use it. She fixes Custas and Tartah then helps the brim hats, saying if you know so much chaotic forbidden magic why not learn how to use it wisely.
The brim hats concede to her reasoning. Iguin revealing this was the crossroads he's wanted to pass but society didn't listen to reason. Yet, she was right.
Olly saves the kids before Easthies claims to remake the Knight Moralis and takes on the brim hats.
At home, the tree is tall and bloomed. Coco immediately rushes to do the spell while everyone is terrified when Olly implies he was too late to save him. Agott tries to stop her as she writes the spell over and over despite it not working.
It was too late.
Coco deflates. Lamenting her mom, if the spell doesn't work here then her mom is gone too.
Olly curses the tree. Says Qifrey has no right to do as he likes. Whether he decide to stay miserable his whole life or be happy and succumb, Olly was supposed to be there.
The former knights moralis find Easthies, he's defeated the brim hats, some fled. When they try to erase his memory he says he knows Vinanna withheld information about the tower of tomes and writes a forbidden spell encasing both her and him. He hoped to end the lies.
Ezrest comes to the Atelier, convincing them to keep trying. Eoleo, taking Tetias beliefs to heart, vows to not misuse their magic to their own benefit, telling his father he won't be crowned prince if it means abusing power.
To be continued...
