After several tries, I just don't think I can manage the Brachiosaur. I tried with Lenna/Celes, WoL, Exdeath, Kefka, and Tellah -- and got nowhere. All 5*, level 80. I thought I could Focus/Full Break/Blizzaga the guy with Celes on Cura duty, but no luck.
My lack of Barrage and any decent physical attacker is showing, and my computer isn't powerful enough to TM grind.
Have you followed Brachiossaur attack pattern?
https://www.reddit.com/r/FFBraveExvius/wiki/missions/trial/1-3
For the easy read:
100% HP threshold:
- Brachiossaur will use dissaster in turn 1, and then you need to start counting turns.
- After that until turn five, Bracchiosaur attacks can be the following:
Normal attack and end turn.
20% chance to do snort (there i suggest you just restart the battle) and end turn.
40% chance to do Disaster and end turn.
40% chance to do Meteor and end turn.
30% chance to do Spin and end turn.
In turn five, Bracchiosaur has 100% chance to do meteor and 20% chance to do Spin in the same turn.
After turn five, when Bracchiosaur does disaster or snort, you should start counting turns again (if Bracchiosaur does any other attack, you dont need to count turns)
50% Threshold:
- When you damage 50% or more to brachiossaur, it will use "charging power" skill. And the next turn he will do ultima (celes runic can absorb ultima (i assume meteor too, if you want to do it in turn 5)
- Theres a little chance that brachiossaur will attack normally. If that happens, next turn will do charging power, and ultima the turn after that.
-After bracchiosaur does ultima, you can follow the attack pattern from before (if the turn bracchiosaur does "charging power" or ultima coincides with the turn 5 of meteor, it wont cast meteor, but after the ultima, it will do meteor)
30% HP Threshold:
- When you hit the 30% hp mark or less, Bracchiosaur will do snort with 100% chance, and end turn.
- After that you must follow the same attack pattern from before. (the turn five meteor applies to snort too)
If you follow this steps, you might defeat it.
If you dont have full break, what i recommend:
- Warrior of Light for full break
- Exdeath for imperil (very usefull here) and blizzaga
- Lid for the focus (if you have a Vaan then a Vaan)
- Kefka for blizzaga and imperil (and elemental chain)
- Lenna with headband and black choker equipped (this is very important!, that way lenna wont be confused or sleep and she will be active all the battle for healing or esuna)
I just tried with WoL (Golem), Kefka (Ramuh), Chizuru (Ifrit), Lenna (Shiva) and ExDeath (Siren) and i did it without any TM equip or materia. Just normal equip and just being careful of not doing anything wrong with turns.