Baron Zeemo Master Swordsman Montesi Spellbook

[Sz4r1ej]

If an allied Baron Zeemo in Defenders team picks up the book and uses beam attack and changes one of the attacks to physical using Dr. Strange's leadership can he use his Master Swordman superpower to get all rerolls on this attack? 

[Thoras]

Yes, with the caveat that you need to use Mystic Empowerment after declaring the attack but before choosing your first target, which means it is changed for all characters in the beam.