“In short, there is nearly no need to take sacred arts that can
access a light cube directly into account for a normal battle. To
put it another way, there is no danger of your soul being
overtaken and brainwashed into an integrity knight in the midst
of battle. However—what if Administrator gave up on capturing
the warrior I chose and simply tried to blow the soul away...? The
necessary command should rapidly shorten along with the lack
for meticulous adjustments of the parameters. It might even
shorten to the extent of letting her finish reciting it while her
escorts battled. I can compensate for attacks based on Life with
equipment and sacred arts as well. However, there is no defense
against an attack towards the fluct light itself. I racked my mind
for a long time when I realized that possibility.”

“...An attack on the soul... that's pretty nasty...”

“Yes. Any sort of master would be rendered powerless with
his or her memories torn away... As such, Kirito, you are the only
one capable of confronting that attack."

(Alicization Rising, 81)