I know we'll never get this kind of rival, but I'd love to see a rival that's kinda like a reverse Silver. The character starts off as basically your best friend and you're having fun and stuff. But then later on in the story, loss after loss, as well as the player character getting constant praise (and being the "chosen one" for the box legend) starts to breed jealously and envy. The rival will start to take more drastic measures in order to win, and even at one point temporarily joins the evil team. They know its wrong, but they are just so desperate to win that they just don't care.
When the postgame begins, their relationship is very strained, but the rival is trying to atone for all the wrongdoings they did during the story; they'll even be a postgame episode, similar to XY's episode, Delta, and Rainbow that deals with them rekindling their relationship.
When the postgame begins, their relationship is very strained, but the rival is trying to atone for all the wrongdoings they did during the story; they'll even be a postgame episode, similar to XY's episode, Delta, and Rainbow that deals with them rekindling their relationship.