The really irritating thing is that Ultima Weapon will do Incubus Tank Purge even if pushed into last phase, it seems. Cause when I ate it the second time on D240, he was already at like 10% left.
Anyway, while I sub-30 the D240 with a realm team in some 20 odd seconds, I had to Cloudburst the D280. Spent too much time trying to survive in the beginning with realm team and that left me no time to DPS. Used Cloud/Zack with Y'Shtola/Minfillia/Cid as backup. Cid as Entrust-bot, Minfillia to cast Hastega then Magic Breakdown constantly. Turn 1 Y'Shtola BSSB or don't bother.
Oh, and Unicorn seems to be a godsend for this fight. Fuck that sap.
I haven't tried yet but will keep Unicorn in mind. The d280, were you able to pull a sub 30 with your Cloud team?