DISCLAIMER

Following /u/NeokerGaray9393 's clear of this CoW with Esther as the tank, I noticed watching the video and pausing every turn for a turn by turn guide is quite hard, specially when you're at work, so I went ahead and created a turn by turn table to help everyone in the same spot. I wasn't the one to create the clear itself, this is the clear video he posted and its totally his credit =)

BUILD

For the team, I used a very similar one as his with one exception, being Wylk instead of Olive:

Kaito, Sylvie, Chizuru, Wylk, Esther, Cressnik

• Esther need as much bulk as possible, since the fight is really dangerous on some turns and if she dies while at base form (1 turn before burst) its basically a lost run.
  
• Kaito had 50k HP (the new VC from the WoTV vs FFBE event helps a lot since it gives 1k hp)
• Wylk and Chizuru are built for full bulk on base form with a pinch of water resist to survive turn 7. Wylk's base form also has an earth weapon. Cressnik and Sylvie are built the same as well, with the exception being Cressnik's shift form using Morgana's rod (pretty much required)
• Everyone with at least -50% wind res. Lots of Photon Cores spread around the team, really important TMR to have here since gearing 3 DPS for fairy killer is hard.
• Chizuru can't have more than 1 source of guts, so if she's EX3 you basically need another card that's not hers. I used Esther's. I also used Taivas' STMR on her base form but its probably not needed.

TURN TABLE

(* bold means action in brave shift)
(** Core means Potion Remedy Antioxidant )

MORALE

Overall, morale wasnt a huge problem. However, there are two threshold I needed to be able to cap damage :

• Turn 3: 150%, unlocks Kaito's setup skills.

• Turn 4: ~190%, the higher the better, I had EX3 on Chizu and ~9.5k atk with full killers and it was still close with 185% morale.

• Turn 8: 200%. The last 50% of health from the boss is beefier than the first 50% because the mitigations are higher, so you need to deal more damage. Depending on gear you'll need Taivas' Spirit, so make Chizuru's base form bulkier since you'll not be able to guard on turn 7.