FFVII Rebirth - Secret Wail Counter In Final Boss

If you use the flower shield to protect yourself against the Wail attack, it will coalesce into an orb of light you can knock back into the boss' lower face to instantly KO it.

[@torru36]

I bet that is Aerith helping Zack out.

[@DrakeyC]

Absolutely, it even has the same flower petals as her attacks

[@PierceArner]

Thanks for getting a good clip of this!
I assume that this is from Aerith's link to Zack in a similar way to how Zack can use a Syngergy attack with Cloud despite Sephiroth splitting them apart.
(Especially since Zack's DMW gameplay in Crisis Core was always about his memories of people, this seems like a way to translate that into his gameplay here, but I'm curious design-wise why you have to attack this one to trigger it and why it's called what it is).

[@DrakeyC]

You're welcome. I had no idea this attack was even a thing until someone mentioned it to me and I tried it out. Between the specific attack used and people being unsure what the barrier is for, its easy to miss.
I wonder why that too. It blocks most other attacks to some extent, but only Wail in particular can be fully countered? I think it'd made more sense for Sephiroth"s signature moves, like Zanshin and Hell's Gate, to be the ones it counters.