>>55099105(You) have Terapagos in your physical possession after capturing it, even if it's not in your direct party, so it's responding to its surroundings. And Terapagos essentially has the mental capacity of an optimistic toddler that sees good in everyone, acting on impulsive whims. That's why its first act when awakened was to approach (You), like a newborn animal crawling to its parent for the first time. It's when it's close enough to powerful Tera Energy that this impulsive personality has a notable effect.
Kieran wanted it to get strong enough to defeat (You) right at the heart of Area Zero, where the Tera Crystals are at their purest and strongest? Fuck it, show off that Stellar Power and go berserk. The Crystal Pool full of Tera Crystals similar in composition to Area Zero's depths has a real strong vibe? Fuck it, let's pull a version of the professor from before they went schizo.
Blueberry Academy has that fucking massive Tera Core, which was upgraded with materials from the underdepths (which also resulted in wild Stellar Pokemon appearing) and it's considered "close enough" in proximity for Terapagos to hear all of Snackworth's charismatic stories and love every second of it to a point where it wants to sincerely believe him, acting on impulse to make those Pokemon appear in Paldea under the genuine idea that all (You) need to do is have that Pokemon's alleged favorite snack to coax them out.
