>>49379460You don't, really. At the end of the game you pick one to join you in your last mission of the story, but they just kind of have a bit of exposition, and communicate telepathically with Dialga/Palkia (only for a few lines of text, its pretty much just to advance the story to tell you what to do next). You don't align yourself with one clan and disregard another, it's pretty much just to decide which box legend you want to catch and which you want to battle.
