Warning: Contains SPOILERS for The Batman.
The reveal of the Joker at the end of The Batman actually completes the Riddler's transformation into a villain, by turning his biggest flaw into a weapon for the sequel. The Batman follows Robert Pattinson's Bruce Wayne as he attempts to catch and thwart Paul Dano's Riddler as the latter wreaks havoc in Gotham. The Riddler's plan involves the murder of numerous important figures in Gotham's criminal and political hierarchy, all with the express intention of revealing the depth of the corruption that has claimed the city.
Interestingly, this puts The Batman's villain on a very similar crusade to its hero, with only the means of their respective missions different. Riddler proves he's willing to kill to achieve his ends, but he still sees himself as something of a hero. After detailing the extent of his plan to Batman, Riddler reveals that he sees himself as a vigilante and that he believed that he and Batman were something of a team. This feeds into the characterization of Paul Dano's Riddler as a brilliant loner whose pursuit of warped justice is matched only by his desire for a friend.
Upon being confronted with the truth, Pattinson's Batman is horrified by Riddler's plan. This sends the captured villain spiraling—at least until The Batman's closing scenes, in which he is consoled by a shadowy figure revealed to be the Joker. Joker's reassuring words complete Riddler's transformation, indicating that he will fully embrace his villainous nature in the future, and it seemingly turns his weakness into an alliance with the Clown Prince of Crime.
Riddler's Batman Plan Echoes Nolan's Joker
While Matt Reeves' The Batman is entirely separate from Christopher Nolan's Dark Knight trilogy, the Riddler's plan contains echoes of Heath Ledger's Joker. There are a handful of similarities between the two characters and their plans. Both involve toppling the balance of power in Gotham, and both villains kill some of the city's most powerful figures. However, one of the biggest parallels is in the way that the two villains view Batman.
Ledger's Joker famously told Batman, "you complete me". This is something that factors largely into Dano's Riddler, too. In The Batman, Riddler uses Batman as a tool to help him execute his assault on Gotham's corruption. Riddler explains to Batman that he sees them as a team, with Batman lending his physical abilities to aid Riddler's scheme. This not only echoes the sentiment expressed by Heath Ledger's Joker, but it shows that Dano's Riddler is desperate for a companion and that he longs to work as part of a team.
Why Dano's Riddler Beats Pattinson's Batman
Throughout The Batman, the Riddler is shown to be several steps ahead of Batman. In fact, Dano's Riddler is only captured in line with his own plan and subsequently reveals that he believed Batman was helping him all along. This not only evidences Riddler's biggest flaw but also goes a long way towards explaining exactly why it helped him beat Batman—he wasn't actually trying to.
The Riddler's plan is revealed to have been an elaborate set-up to kill Gotham's most powerful people and exact "real change", culminating in an attack on the inauguration of Gotham's new mayor Bella Réal and the flooding of The Batman's Gotham City. In addition, Riddler believed that Batman was his ally, proving that Batman was even further behind the villain than he thought. This shows that the hero and the villain were in fact playing very different games, which evidences not only how clever The Batman's Riddler is, but also that the character's need for companionship is his biggest weakness.
Batman's Riddler Rejection Is His Villain Origin Story
While the Riddler is very much the driving force behind The Batman's story, his final transformation into a villain doesn't technically come until the end of the film. It's revealed that the Riddler believes that he's a vigilante of the same caliber as Batman, and that the pair were two sides of the same coin: Batman's physical strength complements the Riddler's intelligence, and so he believed that they were a team. When Batman and Riddler finally come face-to-face, Batman's horrified reaction is the only real hitch in the villain's execution of his plan.
This, combined with his later conversation with the Joker, is the real turning point that will see Riddler embrace his role as a villain. Throughout The Batman, Riddler sees himself as something of a hero, using his imagined partnership with Batman as evidence that he's helping Gotham. Batman's rejection forces him to confront how wrong he was, alienating the Riddler from the idea that he was doing what was right, and starting a rivalry between the Caped Crusader and the Riddler that is clearly far from over.
Joker Will Make Riddler More Dangerous In The Batman 2
Despite The Batman's Riddler borrowing a trick from The Dark Knight's Joker, Reeves' continuity has its own version of Batman's archnemesis, as confirmed by his interaction with Dano's villain. Riddler's shattered belief in his partnership with Batman crushes him, and Joker's offer of friendship immediately resonates with the villain. But, in offering a few words of comfort, Barry Keoghan's (mostly) unseen Joker seems to set Riddler up as even more of a villain for The Batman 2 by offering him the friendship he craves, from a source that will almost certainly corrupt him even further.
While Batman's rejection of the Riddler could be considered the true beginning of the character's arc as a genuine villain, Joker appears to give him an extra nudge. Riddler is an excellent villain in The Batman, partly because he's not aware of the truth of his own nature. In forging an alliance with the Joker, Dano's Riddler will surely learn a thing or two from the unapologetic villain about how to embrace his darker side, and potentially make even more contacts in Gotham's criminal underworld. This sets him up to be even more of a villain in The Batman 2, as he'll no longer be acting under the pretense of his imagined friendship with Batman.
Ultimately, The Batman's Riddler is undone by his one major weakness, in spite of the brilliance of his plan outsmarting even Batman. Although Riddler's plan succeeds in almost every way, his visible upset at Batman's rejection proves that he needs to feel recognized and appreciated. However, by offering his friendship and posing a riddle to the Riddler, Joker turns this weakness into one of the villain's biggest weapons for a sequel to The Batman.
