He had found a promising avenue of pursuit.
The predicament of the Divine Doctor, having left no physical clues, was fine. All Rui had to do was explore the minds of the denizens of the Valley of Prisms rather than the region itself.
He had confirmed that they remembered the Divine Doctor well. The question was whether he ought to extract information from them effectively. They had terrible communication intelligence. Thus, he could not particularly rely on them to convey accurate details to him even if they recalled the Divine Doctor's visit to the Valley of Prisms.
Of course, he made sure to verify this nonetheless.
He sharpened his eyes, conveying the image of the Divine Doctor to several herds of catoblepas.
Their reactions did not change.
"MOOOOOOOOOEEEEAAAAUUUU!"
They mooed in emotional distress.
BADUMP!