What does "which" refer to here?

In a logical sense, I personally agree that faith is, most importantly, the "devil's masterpiece", so you could be right, InfraBlue.

I'm glad that finally you've come to this conclusion.

Thank you.

Thank you both.

Reaching agreement doesn't make it "right", Ori. Or what the writer intended. But as Infra has alluded to, that niggling little detail will never be known.