Regen from organic decomposition vs higher AP, who wins?

[Threemagi]

So there's a character who can regen from cellular/organic decomposition (It looks like she turns to dust after being hit by decomposition attack)

Regen-ning character has 6-B dura. Incoming 'higher AP attack' is High 6-A.

Now, who emerge victorious? I think High 6-A attack would be the victor here. But I just want to make sure.