Beat Despair Sephiroth, but no mastery; couldn't DPS him down before Octaslash #10. Strategy was this:
Alphinaud: Drainga, Meltdown, Mako's Might, has Deployment Tactics and Aerial Burst
The lynchpin of the strategy, since a lot of the damage is through Deployment Tactics. This is a fight where you really need to keep things carefully, so Sephiroth beating himself up helps.
Eiko: Protectga, Curaja, Ace Striker, has her USB
The instant cast USB w/ Last Stand and Haste are incredibly valuable. Casting that as soon he fires off a Dispel of Despair, as it gets me back on my feet, provides a cushion for whatever else he may throw at me, and my only form of Hastega.
Yuna: Ultra Cure, Shellga, Knight's Charge, Miracle Veil and Tenet's of Fayth
Pretty much pure healing duty, her BSB and SSB2 both see use depending on circumstance, shouldn't have to go into details.
Arc: Curaga, Curaise, Battleforged, Word of Kindess and Renewing Rain
He has Magic Blink that also provides Shellga (good for freeing up a turn for Yuna to do a medica or something) and Heavy Regen, as well as an instant Medica to back up Eiko that also provides Blink as an extra cushion. He ultimately died mid-fight due to bad RNG, and I wonder if he would have survived if I had given him those 6 extra levels (he was 93), and his 3* record Spheres (makes him go from 4800 to 5300~ HP, so meaningful difference) If he was alive, it could have made the difference too since he was using Vanille's RW mostly for DPS Purposes, plus adds another hit for Sephiroth to smack himself with.
Tyro: Full Break, Magic Breakdown, Dr. Mog's Teachings, Sentinel Grimoire and his BSB
Should be straight forward what Tyro was doing; he always does the same thing these days!
I RW'd Vanille's BSB because it's instant, is a healer BSB and has damage attached on one of it's commands.
I don't know if this team can actually DPS him down fast enough if I manipulate the ATB more with Deployment Tactics, have Alphinaud use Aerial Burst earlier in the fight, and keep Arc alive to get more turns of Vanille off, so the question is "are 30 4* Bravery Motes worth the trouble?"