Amy set up the circle. She had to do this all by herself while getting new useful stream of information into her brain which was quite enlightening. She left out some details from her conspirators but promised to reveal it in due time. It is best to save up that rage for the best time.
Leon has not been in contact with them since she revealed her plan. He didn't even attend the discussions. In fact, Rufus speaks for him telling her that he is insanely busy.
The entire Conspiracy Theory club were in on this too as Amy knew that having more people would make things much easier and safer. But this was planned behind her back as Leon started telling everyone. Leon even went as far to create convincing illusions of them to act in their place while they work on the preparation just to hide their plans. In addition, the circle is upgraded by Alabaster who got rid of all its inconsistencies so it should work with much better results. Unfortunately, he's too busy and decided to previously use the default one since he never even tested out the new ritual to trust it.
Honestly, this is all against her better judgement. Why did they not get the adults in on this?
One, it is suspicious. Amy got her information from an exiled doctor and a time traveler, both of whom she refused to reveal. She does not wish to be in a position where anyone would question her at a large scale.
Two, no one would believe them. Amy worked her butt off with the research and the whole club knows it and trust her. The adults are not gonna trust a group of young teenagers to do something dangerous and would stop them before it even starts. And as much as she hates to admit, she would do the same thing if she wasn't so desperate.
Three, everyone here has a vendetta, so they don't want anyone else ruining their plans. Amy is not even exaggerating. The level of commitment and energy is off the charts. She may not be personally close to Margaret Lune, but she is a kind, non-judgmental soul who doesn't deserve to die.
Four, they could be next and not expect it.
To be honest, she is reluctant and initially against the idea of bringing more people into danger. The reason why she decides to recruit Rufus and Leon is because she knows they will survive this, but she also relents because of them. Amy's faith in her friends didn't waver but she is apparently the only one worried that this ritual could fail and kill them. She could have waited longer but there is much at stake and the Ripper's three years of Terror was a memory that many never forgot, and the world barely recovered from.
After finishing the set-up, she noticed that there is still daylight. She is at the woods behind the school. The barrier has weakened a bit since Margaret's death. It is also under investigation as it was barely noticeable at first but then it slowly started degrading. It was because of the Ripper. He moved very quickly to break through the barrier just small enough for the damage to practically be invisible.
After checking for anything she left out, she smiled and clapped her hands, "It's done."
*
Now, it is late at night and all of them are standing in position. Nathaniel and Sabina are both the sniper and the lookout. Theseus's ability is constantly on so that the moment the Ripper decides to materialize and pass through the circle, he will be crushed by the extreme gravity trapping him in the circle until he decides to go transparent but still would be trapped into the circle. There would be no way out. Melissa is on standby in case someone needs her as she is the healer. Everyone else will be focusing their energy on the ritual's integrity.
They don't know this, but Boris left a box that poses as bait that is also made of the flesh of a Ripper victim. No one knows this of course and she intends to keep it that way.
Leon, Rufus and Viola are at the circle putting their magic into the smaller circles. Some of the remaining students also provide magic as a precautionary measure. Boris is far too worried to let a bunch of students risk their lives, so he is also on standby but is ignored. Viola is probably too angry to take notice. She is going to have to discuss this with her once it is all over.
As for who gets to purify the poltergeist, the task can go to either her or Viola. But because of her exhaustion as well as her constant use of magic on the marionettes that she spends all year making for Boris and Alabaster, Viola would be dealing with the circle while Amy would be purifying it. Literally everyone voted on it though the reason why Amy was chosen was because of her strong-willed personality. It is also noted that Amy has better precision and better concentration, so she is tasked with killing the being.
"He's coming!" Sabina yelled and ran back breaking Amy out of her thoughts. The circle is activated bringing the poltergeist in. The figure is again brought in the circle and materialized to leave but the moment he did, he collapsed on the ground and is unable to get up. Theseus's ability is doing quite well. Impatient, he turns transparent again but is unable to escape the ritual. Realizing he is trapped; he began to scream but can barely get a voice out like this. His humanoid figure starts to show, and his face looks pissed. The circle is also modified to drain his magic as long as everyone's collective magic would surpass his. Even though his magic is his own, it is like a battery. It will eventually die.
The ghost has an agenda, an unfinished goal and he won't stop or rest in peace until he kills everyone he hates. Since he is technically different from any other ghost or spirit, they could only drain his magic and make him disappear out of existence. So, in order to kill him, the more he stays in the circle, the closer he is to disappearing for good. Amy has a plan to keep him there and now she's going to reveal his story in front of everyone.