been shuffling around my original team ideas for kai's pkmn verse & have landed on this for the first season,,
leading up to reaching the masters eight his team consists of talonflame, persian (alolan), houndoom, zoroark, absol, bisharp (shiny).
upon being retaken in by borg his talonflame gets replaced with moltres & he throws talonflame's pokeball away to takao.
before the finals, thus before facing them in an official setting, he calls out his former teammates & challenges them on lake baikal ; takao uses kai's abandoned talonflame in the process of defeating moltres.
talonflame returns to kai's lineup after the defeat. kai uses moltres to unleash havoc upon the abbey & releases it in the heart of borg, letting it rain its revenge as he leaves borg behind.
borg still have their claws in moltres so they're able to extract the energy it stole from other pokemon, but it breaks the tech keeping it bound & it flees borg for the first time in nearly a century.
in the intermission of kai's first finals battle, soichirou offers up a clone of the moltres borg had kept under lock & chain. it's unstable. kai takes the ball. he does not use it in battle. ( he never uses it in an official battle. it is never officially registered among his pokemon & thus he breaks the max-6-pokemon carry rule. )