Aquarius C5 is the most difficult boss of this CB. The unique mechanic of this boss is that if its UB causes your characters to fall below 40% health, they will become stunned. The only high damage team, shown here, carries a heavy element of RNG based on whether your characters crit at the right times (thus absorbing enough HP to avoid being stunned by the boss's UB), as well as who yukari heals. Bad rng can cause characters to become stunned, or in the worst case, die, causing your damage to plummet.
The other option is to use magic team on this boss, but the damage tops out at around 1.6M.
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