When it comes to the vulnerability of lucifer around Chloe and in this episode he becomes invulnerable, what if Chloe manifested her desire for him to be strong. She has wanted to connect and be let in by lucifer, in the past, and felt insecure about the relationship. But when she sees him insecure she wants him to feel empowered. Therefore, it was not lucifer's change of heart that keeps the bullet from killing him, its Chloe's desire for him to be the angel he is with the strength and power he deserves.
Yes, the manifestation can come from the angels self reflection but she has a super power of magnifying that self reflection. Amenadiel is the favorite son and people feel calmer in his presence but the one time he works along side Chloe, his super power is magnified. Yes it can be questioned of whether it is her presence that magnifies his abilities or the fact that since they are nuns they are already invested in the faith. but when she is close by the nuns focus on their faith reflected by Amenadiels much more than ever seen before. Amenadiel has been seen to calm Dan after he returns from taking charlotte to heaven. He has calmed maze and linda in the desire for them to have faith in what he is saying and what they want to believe. so the power has always been there.
When we look at Cain and his relationship with her, it is the love he has for her that takes away his mark. She magnifies his desire to be mortal and by doing so breaks the curse. She wants him to be the man she can rely on and she believe him to be the good man he has never seen himself as. Someone worthy of love.
I think this is how she will be the key in defeating Michael. She has a super power just as subtle as the others that we have to look for to see. She has the will to overcome any fear he could impose on her. She could be the manifestation of freedom of will.
