"Exhaustive."
"Ruler."
Liu Di narrowed his eyes, his mind racing.
In every game of Go, Gu Fan had to place a stone in that position?!
Ruler.
Cosmos.
Liu Di thought rapidly. This clue was like a sponge, and he used every ounce of brainpower to squeeze every last drop of water from it.
Chinese Go.
A Go board had 19 by 19, for a total of 361 points. Beginners could never remember the names of the positions, making it difficult for Go masters to teach.
But the ancient Chinese were extraordinarily wise.
They turned those 361 points into various Chinese characters and linked them into elegant verses.
Such verses were called board-writing poetry.
A derivative culture of Go.
'The north wind scatters snow; in winter's cold, the lone pine revives. Fine liquor warms the secret room; we tap the board beside the brazier.'
'Exhaustively examine the forms of heaven and earth; the celestial courses naturally correspond. Yin and yang rise and fall against each other; prediction grows vague.'
And so on.
Liu Di murmured to himself, "Gu Fan is a refined woman, a gifted scholar deeply versed in ancient Xia culture. Ruler and cosmos."
"This came from board-writing poetry."
"And it is an extremely obscure version of board-writing poetry from the Ming dynasty, written by Wu Jinshu."
"Ruler and cosmos are respectively the final and second-to-last characters in the lower-right corner of the board."
"That is the lower-right corner of the board, a narrow place—the boundary."
"Exhaustive Ruler... the stone is not on the board. Could that mean beyond the boundary?"
"And what does this board refer to?"
As Liu Di pondered, he suddenly saw the reflection of his own features in Red-haired Peach's pupils.
He magnified the image and, within his Right Eye that flickered with violet light, saw