As a standard permanent it seemed a little OP. As a shield this is actually pretty cool! It gives a nice answer to phase shield.
However, given that it protects from a broader spectrum of sources, it should be a little more expensive than its
cousin. This shield essentially protects you from any kind of attack so its like a combination of mirror shield and phase shield plus poison reflect. Sans immaterial.
Quite powerful, so spamming may be a definite concern, much more so than phase shield which relys on the fact that spells and poison can bypass it. This will take some work to balance, I think.
All in all though, very cool concept.