I RAREly use the twins, I don't even have BT+3, but once in a while when there is a 3 target fight that are not add based they can just blow them up without worrying about the target number requirement for their stats.
Leila on the other hand also completely trivialize the dangerous part of this fight. Since there are three target and the team does not delay them, Leila will just break their collective turns into one at a time. It does not even matter if they have AoE HP damage, Leila would just heal the team back up and fulfil the orb at the same time.
Edgar is pretty much there to put down the magic imperil on top of Leila + Twins' respective imperil, so they can get all the imperil BRV bonus up from both element and attack type. Also, he has great splash and 100% AoE damage to go with his debuffs.
There are a lot of ways to cheese this fight but ultimately it really is not a hard fight. Other great AoE dmg dealers like Yda, Vivi, Strago will finish this in no time.
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