Yea I know, but still, it is a pretty convincing initiative to do something.
Edit: I have an idea of how the crystalline demons would have a weakness. Since all crystals have a frequency where they shatter (I believe), maybe we can use sound to defeat the blue crystalline demons. Of course though, the laws of nature of thier universe or whatever may keep that from happening. However, I am not sure how to do something which would generate a sound that would shatter those blue demons without shattering the immersion at the same time. It is just an idea though.