I'll give you info from the strategy guide.

19k hp for wutai solder geng, 61k hp for crescent unit phantasma, 94k hp for crescent unit circulus, and 48k hp for nandi. Equip blaze armlet to absorve tri-fire damage, in early part of missions. Graviga is not as effective in the main part of the mission. For the final battle, replace blaze armor for prtoect ring or shinra beta+ to get defeense, and attack with graviga. Graviga and costly punch are good. If you get no mp cost bonus from dmv, take advantage with tri thundaga or energy attacks. Use regen in place of status ward. I typed this while not lloking at the screen, reading the guide, ther'es typos i dontw anna fix them tho