Hey Teo, what's your friend code? I saw a 'Teorem' with SSII a few months back, and now he has Boon. I thought that was you, but apparently not, since you don't have SSII? I'm 9UzH. I usually have Boon up, but I also have SG, HH, and recently War Dance.
As for the fight, any reason you're not using Galuf RW? The SB is tricky since you can't refresh it while still active, but luckily, you can have one person dead and still Champion. You can start your second UF on another character right before the first wears off. When Vossler kills UF1, he'll start hitting your UF2, which will save you on the KO front, and you basically won't have to heal much in the second half of the fight. This assumes you can kill him before your second UF wears.
Sazh - Armor Breakdown / [flex] (UF1)
Vaan - Steal Power / Tempo Flurry
Ashe - Ruinga / Waterja
Tyro - Lifesiphon / Protectra (UF2)
Mog - Curaja / Dispel
Some notes:
- Start UF when you feel you can't keep up with the damage (~60-70% Vossler)
- Use Boon + Protectra + HH at the beginning. This will keep damage way down
- With a decent amount of AoEs, Sazh should easily get another Boon to help you burn him down late in the fight. Just make sure you use it before he goes down.
- You won't have to heal much once your first UF goes up. Mog can concentrate on Dispel