They perform some more magic tests and run out of mana and recover mana and perform more tests and a second sleepover could be fun but it's decided that people can do coordinated tests in their own places and there is not actually a need for them to all be in the same place. The Maxwells' driver takes Jess home (and Maya, too, if she prefers that to staying with the Maxwells but they assure her she's welcome to stay there), then takes Sadde, Theo, and Tyler to the Farron residence, where Sadde prefers to be dropped—he'll go to his place by public transportation, he'd like to talk to the—twins?—yes, thank you, it was a pleasure meeting you.
"Anyway, I guess we could try to build a spell that specifically looks for Yue."
"Yeah," agrees Tyler. Tap tap. "Does 'yang' mean anything to you, Cerberus?"
"It's kinda weird that Yue has a Chinese name and you have a – what, Latin name? I guess it makes sense with joining Western and Eastern culture, but I'd expect you to be Sol or something."
"Does he assume other forms at all frequently, like you're sometimes a bear?"
"We should first see whether we can build one that finds someone whose whereabouts we do know—like you, or Kero, or Willow—before trying to get Yue."
He starts scribbling.
"Dash, Maze, Move, Return, Through, Time," says Tyler, "look like cards, or concepts, that could be useful."
"Dash because movement, Maze because they might be hidden and mazes are conceptually linked, Move because movement and distance and such, Return because we want to be able to retrieve or at least find them, fits for Yue and Cerberus, Through because it might not be a direct path, might be able to cut through obstacles or something, unsure, Time because we could trace their path from a known location through time."
"Okay, reasonable. Seems like both Sun and Moon are called for, then, and Wind..." He starts writing out a spell that could work.
Eventually he has something. "Okay, maybe I should try this without any scrolls, just see if it works, yeah?"
"Sounds sensible. We haven't had any side-effects from underpowered spells yet, as far as I know."