I used Lightning/Sazh/Hope, started out with COM/SYN/SYN, then once I had haste/protect/shell on everyone switched to Rav/Rav/Rav, then when he was going to do that big stupid attack where all the energy balls rain on you I switched to com/syn (sazh)/med, then when my people were healed fully switched back to rav/rav/rav, then com/com/rav once i staggered him.

I might add however that I used a Fortisol before the battle and that the battle went pretty slow for me (I managed three stars). I also died like five times before winning.