That is his past self, or perhaps his future self.
Fragments of memory from the Heart Burning Corridor suddenly surged forth.
At the same time, those memories sealed and obscured in his mind burst forth like a breached dam, weaving and colliding with unprecedented speed, recombining.
What he had experienced, and what he had not, stemmed from the incomplete memories within the River of Space-Time, rapidly piecing together in his mind, leaving nothing out.
After a moment, he suddenly looked up, and his eyes no longer held calm and depth, but were filled with an indescribable horror.
So this is how it is...
In an instant, the shackles of time and space were completely broken; the fog of the past dissipated, the trajectory of the future became clear, and his memories fully revived, understanding instantly the cause and effect of the ages, why he was so certain of victory.
He remembered how he won that battle.
