In what way does simply being "supernatural" make them immune to conventional weaponry? Is a griffon immune to guns because it's 'supernatural'? It's made of flesh and blood, supposedly, so is its skin just so strong that it deflects projectiles? 'Supernatural' is about as descriptive as saying, "it's pretty sturdy." How sturdy. Why? I assumed they were incorporeal because otherwise they'd be so tough or have some sort of "supernatural shield" which is not described anywhere in the Int-Check setting.

I can change it, nevertheless, but I'm quite curious to see what else is so unacceptable that you request I start from scratch.