You can't hide. In addition to ordinary physical damage, E can also avoid physical attacks or physical skills with certain skill bonus, such as Q (additional damage for next attack, physical bonus) of monkeys or Q (long-range attack skill, physical bonus) of captains, or even R (big move, physical bonus) of The Grand Duelist. It is skill that causes spell damage and cannot be avoided.

The R in Knox's hand causes real damage, which is neither physical damage nor spell damage, while the E in the weapon is obviously only effective for physical damage, so it is invalid when facing the R in Knox's hand.