This is the Impossible level raid for the latest story event (which was really wonderful by the way).
Sadly I didn't get Selfira nor Elta so I wasn't able to try and do a "story" fight. I just have to settle with Nio. Her Coma does not get removed by the 50% transformation. It was just the usual RNG. He does not remove any local debuffs in general.
Grand Rosetta is also good for this fight as it's very easy to get 5 stacks on the latter half of the fight. Lennah is also very good in this fight.
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