He pretty much says constantly that he'll be the first to die if a fight breaks out so there really isn't much focus on what he can do.
Crime scene forensics with flasks filled with chemical solutions to check for residual magic energy to determine time of death, making on the spot, but poor in quality, bounded barriers, excelling in meditation and sleep management, and....yeah. His cigars are disposable mystic codes.
Waver is never going to be able to defend himself. Unless he ends up
in the main universe.