The confirmation i could get is that Assist skills providing combo hit/double/triple, Defense up and attack up should only apply to the kami/soul herself.
Some special effects affect the whole group, there are usually weak or limited in use.
If a kami's assist provides attack up permanently for the whole group, then it should be a bug, unless it is described as those.
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3-4 events more, you will be done
Ok Hercules, 2 more events then.