LogFAQs > #893771803

for Cloud USB retaliate, apparently some 5* skills can still target party members, like spellblade and darkness. flare strike in particular would work best with it as it's 5 hits. there's also Prishe's lv99 RM, which is 3 hits and anyone can use. or since you're likely using Zack, quick hit maybe? since that's 2 hits and instant.

the setup is as you said, just Cloud USB and Zack chain. haste is also important. i'm not sure about what the best possible way to set all that up is. probably involves Reks BSB as best case scenario, as he has a stacking atk buff+hastega and can use flare strike. probably reks with Dr mogs+flare strike, Zack with mako might+quick hit, dived Shelke with Prishe lv99RM+wrath/entrust, Cloud with truthseeker+retaliate/OD, healer if needed/another spellblade if not.
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Grats to BKSheikah, a guru ahead of his time.
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