Mastered and got FULL medals on the latest Ultimate with the following team,
Retaliate Advance ftw again! And this time I think its even the safest strategy around. At first I thought I'd have to knock the boss out of its form each time and make it susceptible to physical damage. I used two characters with Diaga because of this. HOWEVER, you actually only need to do this the first time! Even when the boss eventually reverts back to its Female form, the retaliate strikes will still damage it without the bosses counter going off! So the fight was super easy with no timing required because I never had to worry about accidentally striking it. Just Walled up , Booned up and Advanced up the first round while Aerith diaga'd it. Then diaga'd once more before using retaliate with cloud. Everyone else attacked cloud the entire time accept Yshtola who would curaga every turn until gaining a soul break bar to SS2 a second time to be safe.
Oh and sazh used magic break (for the medals) once before unleashing his double cut onslaught on cloud.