Exactly. You can chart his deterioration across each game. >Origins
He's a smarmy, cocky, actually effective hacker/extortionist. He's fit, handsome, has good posture, and actively fucks with Batman purely for his own amusement i.e. Mocking him for dramatically opening doors, making a loud noise to distract him while piloting the Remote Controlled Batarang, etc. He collects data for arguably a good cause and when he's thwarted he doesn't even raise his voice.>Asylum
Full-blown Riddler. Same cocky attitude, but clearly more obsessive and petty than before. Wears the full suit and still grooms, and bloviates about his own abilities and meager accomplishments whenever he gets the chance. Hates Batman and starts to break down when he closes in on finding every trophy.>City
Unshaven, skinny, doesn't sleep. He's started putting people in danger now to get to Batman. Goes out of his way to hide 400 fucking trophies in every inch of the city, including in the lairs of the other villains, AND even makes a set to torture Catwoman because he needs to prove that Batman has inferior taste in women. Grandstands just as much, and now actively puts Batman down. He sounds pissed off for the entire game and starts coming unhinged from basically the moment you start solving his riddles, two of which are legitimate death traps that have no solution, and when you cheat them he calls you out for literally doing the singular thing you could do to survive. >Knight
A literal sewer-dwelling freak who thinks a fucking Hawaiian shirt that he decorated himself constitutes a supervillain outfit and is so desperate to beat Batman at ANYTHING that he's resorted to making racetracks and calling him a moron if he doesn't drive fast.