Photon rifles. The Dragon is a Lancer, so you should definitely avoid having an Archer in your front lines. Sure, Ea can wipe the floor with Saber and Berserker, but it's not as great versus Lancer; and even if you have Kaleidoscope on Gil, you'll still need a turn to get NP charge.
(If you haven't faced Glorious Rome yet, it's only two battles; 1st versus a giant Dragon, 2nd versus Ceasar, Nero's uncle, and Romulus.)