For Braska's Final Aeaon its Jeckt(i cant spell today)if you have anima and have Yuna in Arouns grid and have her powered up alot and used alot of time in powering up Anima 3-4 hits with anima's normal attacks will defeat him.

I havent done this a friend told me this stratagy(he had over 120 hours worth of gameplay on his file too).