Tetrayon-Nine

The planet Tetrayon-Nine was the origin of the game of Chellt, which Century Smith once taught Briar. It was a variation of the game of chess involving time loops, suggesting some aptitude at temporal manipulations from the natives of Tetrayon-Nine. (PROSE: Century Smith and the Time Terror)

Behind the scenes

Tetrayon-Nine was originally mentioned in a The Crew of the Copper-Colored Cupids story predating the appearance of Jenny Everywhere concepts in the series, The Frost King's Treasure.

There, Alistair Neezley claimed to have once “tamed glorks in Tetrayon-Eight – or was it Tetrayon-Nine?”. Other planets in the Tetrayon system would be mentioned in other Cupids stories, including Tetrayon Four in The Arena of the Detraxxi (once more as a place Neezley falsely claimed to have visited) and Tetrayon Six in The Penultimate Pursuit (its first mention in a context ensuring it actually existed as more than a figment of Neezley's imagination).