Real swords were used in close-up shots for authenticity. This risky decision resulted in Jonathan Cake being cut during filming for the first episode. The cut became infected and Cake required hospital treatment.
During the final battle between Antony's and Octavius's armies, Tyranus removes two silver emblems from his chest to denounce Antony and fight for Octavius. In the next shot, they are there again. Later, they disappear once more.