got it done with 1 second left on Squall's Doom timer. had to bring Y'shtola for Stoneskin II, Amarant for his Shellga + High Regen relic, two separate group heals (Tyro w/ Healing Grimoire memorized and Terra geared as a red mage w/ two nukes and Bard's Bracelet), and Squall w/ Cutting Trigger to burn Exdeath down once he switches to his low HP AI. i brought more Breaks this time (Full Break / Magic Breakdown / Power Break / Heroic Harmony RW) since he was disspelling my Shellga/Wall (both of which i brought anyway this time around). with full mitigation up he was nuking for ~200 damage. was pretty tough keeping everything up tho. considering i only had 1 second left on a Doom timer, i maybe would have been safer if i had brought more DPS and less mitigation.
got it done tho.
still haven't beat Omega, don't think i'm going to bother, what an annoying/gimmicky fight. this Exdeath fight is tuned much better than Omega... was actually enjoyable instead of rage inducing.