Use Byakuren's Makai Seduction or Charming fragrance or other weapons that inflict those status effect on Kaguya.
[user (ThirdDiary)'s strategy.]
Recommended party : Alice, Aya, Sanae, Nitori, Sakuya/Byakuren* (i used Sakuya)
Formation : Sunshine Lunch
Equipment specs :
Sanae with Paralysis resist
IND+ gear on Sakuya/Byakuren or Aya (increase status inflict chance)
Sakuya w/Aeroknife. Drops from Wyverns. Otherwise use Byakuren. Byakuren w/Charm inflicting skills.
For this strategy. Your main priority is take out Eirin. Unfortunately, she is backed up by Kaguya's 1000hp heals & atk/def buffs. So start off the battle like this
- Alice cast Horai Doll (Decoy),
- Nitori cast Elemental Bullet (Fire) *Kaguya & Eirin are weak to fire
- Sanae cast Wind of Swords (Phys.atk buff)
- Aya use Poison Beak (on Eirin)
- Sakuya w/Aeroknife charm inflict (on Kaguya)
Depending on whether or not charm is inflicted to Kaguya, you may have to reload your game (due to Kaguya buffing Eirin). If charm has worked, proceed to the next turn.
-Alice cast Marionette Parrar
- Nitori use Spitfire -w/fire enchant- (on Eirin)
- Sanae cast Wind of Shield (Phys.def buff)
- Aya spam Poison Beak (on Eirin) until she is Poisoned, then use hard-hitting single target skills only.
- Sakuya can now help with beating up Eirin. Use Dual Raid/Poison Bite to assist.
Important: You will notice that Kaguya will hit Alice (decoy effect) even while she is under the effect of charm.
(If decoy is not active, she will 'hit' herself and charm effect will disappear. Make sure decoy is always on)
Things should be less difficult now. Note that the number of times charm will work on Kaguya is fairly limited (1-3 times) before she gains resistance to it. If re-charming her doesn't seem to work, focus on poisoning Eirin instead. And If you're feeling chivalrous, use Sakuya's 'Collision World' to prevent any sort of healing and use hard-hitting widespread attacks.
Once Eirin's hp drops below 75% ish, she will use Starlight Arrow. This could potentially wipe out your party. The best way to counter it is to use Alice's 'Marionette Parrar' beforehand to shield everyone from the blast.
Also Eirin or Kaguya will throw paralysis at you. That's where paralysis immune comes in handy. I highly suggest having one on Sanae.
When Eirin is killed, Kaguya should be fairly easy.