The circle of protection created by the wings of the Hashritu. Nothing harmful can penetrate it; four-winged Guardians have been known to keep their charges alive and well in water, under spell-attack, in the middle of fires, and under hail of bullets.

As for what happens to any attacks that simply cease to be when touching the caim, it is theorized the Guardian wings actually generate an invisible portal to some unknown dimension, where all the bad stuff simply goes.

Of course, that doesn’t explain how some things ricochet, but it seems the wing-wielders have some control over that.