00:00 - Eirin Yagokoro
At beginning of battle, Tewi inflicts 5 level of Yin/Yang ATK DOWN. This makes everyone doing a pitiful DMG. You can try to use ATK Buff to cancel her debuff. Or endure until the debuff wears off. Or just do full break. Eirin + Medicine should teach them some lesson. Very easy.
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01:15 - Kaguya Houraisan
Standard 2-wave boss battle. Kaguya can solo one boss wave if she is on full spirit. So just bring extra unit that can solo the other wave. But remember that the enemies have high resistance to Normal, Slash, and Ofuda bullet. Make sure you avoid bringing unit with that bullet type.
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02:30 - Fujiwara no Mokou
It's just simple battle with Kaguya. She doesn't have special gimmick so you can just gang her. However, if Mokou is properly equipped, she can solo this stage. Generally you need Spirit Up, Yang ATK Up, or ACC Up. The requirement is quite high so don't force yourself.