The rival.
Especially the douchebag Machiavellian type rivals that the main character ends up friends or teaming up with after the main character 'proves their worth' to them by being stronger. No character growth outside of now they work with the protagonist.
I really want this trope to be subverted one day, like the douchey rival shows up and everyone is just like "Wow what a dickhead" and just relentlessly bullies him until he goes away.
Unironically one of the best rivals is also one of the originals: Gary Motherfucking Oak. Starts off as an asshole rich kid, but after getting life experience he gets over himself. More of a character arc than Ash had in twenty five years lmao.
lol goddammit i just finished saying this. should have checked the thread fully
Gary gets a pass because he has legit growth and stops being a douche