Just prefacing that my team is very strong and yes, wallet powered, but I was nowhere near able to clear the fight on Wednesday. Now with the level 55 statstreams, I was able to skate by with a messy solo crash clear using my 207K power team.

Here are some of my learnings from multiple attempts. I hope with some optimization, more people can have a shot at clearing this fight!

Prep:

• All characters were over 5.4k HP, Aerith was at 6k
• Aerith had 1.9k HEAL stat. She needed to heal at least 2K HP with each Curaga, otherwise the run wouldn't work.
• I built Butterfly Edge on Cloud for the PDEF barrier. I don't have a single copy of Mythril Rod RIP.
• Torn Wing (the free weapon) on Sephiroth would have worked too, but because he was my heaviest hitting damage dealer, I kept Aonibi on him for the MATK buff.
• Cloud carried Triangle sigil, Sephiroth had X sigil, and all three members had Circle.
• Cloud - Ramuh, Sephiroth - Shiva, Aerith - LB (I accidentally brought her ATK LB instead of her healing one. Don't be like me)

Healing Efficiently:

Play manual as Aerith for 90% of the fight

Save all ATB until he does Heartless Archangel (team HP goes to 1) even if it means overcapping on ATB. Right before it hits, flip to Defense stance so that the moment the animation ends, you can start spamming the Curaga button.

You'll need to flip back to Attack stance as soon as the game registers your heal, so the stance can keep building.

When Aerith's ATB is at 4.5 bars, flip back to Defense stance and spam Curaga until it goes off, then flip back.

You should be able to heal THREE times (~6K HP) before he does Shadowflare.

Keep on repeating this every time you heal throughout the fight.

Damage

I didn't optimize for wind damage so I just broke his sigils as quickly as possible so I could heal/max DPS. Cloud just did Thunderstrikes and Sephiroth just did Frostblade the entire fight.

Big damage came from summons. Cloud carried Judgment Bolt and Sephiroth had Diamond Dust. Use them as soon as they are available except during Elemental Infusion (null to all elemental damage).

Octoslash phase:

As soon as Sephiroth begins to cast Boundless Strength (preferably before he even does), swap to your Barrier caster (Cloud in my case) and start building ATB.

He will target one of your party members (the one with the lowest current HP).

You need to ideally get off TWO casts of PDEF barrier on that party member (potency: high) before Octoslash goes off. Don't forget to switch back to DEF stance before it hits.

Pray.

Rotation

Sephiroth will do a Heartless Angel (target 1 character for 1 HP), followed by Octoslash. You need to get a high potency barrier on them and heal them to full health before it goes off.

When he does Heartless Archangel for the second time (all party goes to 1 HP), he'll then cast Masamune in Waiting, so just break sigils quickly and then you can heal during the break.

Rinse and repeat and hope that your DPS survive long enough to kill Sephiroth. Don't forget to summon again when it's ready.

DPS Race

After the 3rd Octoslash, Sephiroth's attacks start to become unmanageable, so he has a soft enrage in the sense that you need to kill him before he kills you.

In that way, you can try to get him to target your healer first for the final Octoslash by having them have the lowest current HP, but it's risky. Having Aerith die first (staying true to lore) is preferable at the end of the fight so that your DPS can continue attacking. There should be one more Masamune in Waiting where you can break and dump all your last damage before he kills off everybody.

On my first clear, my Sephiroth was the only party member standing at the end with just 1 HP left.

Hopefully this helps anybody who might be close to clearing the fight but just needed the extra push with lvl 55 statstreams! Good luck!

https://preview.redd.it/kb4k1fe101ub1.png?width=2796&format=png&auto=webp&s=6223f48452db7bd73efb32852531f3bd3878f6e3

https://preview.redd.it/wubs2yl201ub1.png?width=2796&format=png&auto=webp&s=540facc3538ae24fefe8350ad3e68b0ab71f3899

https://preview.redd.it/mjraru9301ub1.png?width=2796&format=png&auto=webp&s=54c8f03710481070e6cd523f6a772c976b516a7c