Tetrayon-Twelve
From Jenny Everywhere Wiki
On Christmas 2021, Prime Universe time, the skies of Tetrayon-Twelve were the location of a battle between the Detraxxi (trying to bolster their power so they could claim the title of Supreme Cyborg) and Century Smith and Briar. (PROSE: The Winter Quests)
Behind the scenes
Other planets in the Tetrayon system were mentioned in various other The Crew of the Copper-Colored Cupids stories, including Tetrayon-Nine in The Frost King's Treasure and Century Smith and the Time Terror, Tetrayon Four in The Arena of the Detraxxi and Tetrayon Six in The Penultimate Pursuit.