Riddler

[3][4] After a teacher announces that a contest will be held over who can solve a puzzle the fastest, Nigma sets his sights on winning this, craving the glory and satisfaction that will come with the victory.

In the end, his actions turn out to be a front for his attempts to find the hidden treasures of "Scarface" Scarpelli, a Gotham City gangster who lived long before Batman's reign of crimefighting.

[15] After Harley Quinn briefly breaks free of her devotion to the Joker, she attempts to hold up a large party at Wayne Manor, only to find that the Riddler is targeting the building also.

The two gangs engage in a firefight, but Harley gains the upper hand when Big Barda (who was secretly allied with her at the time) interrupts the conflict and captures the Riddler and his men.

In addition, Batman warns him that if he reveals the secret, it would give Ra's al Ghul a vital clue that he used a Lazarus Pit without his permission, and the League of Assassins would subsequently retaliate against him.

As revealed in Batman: Legends of the Dark Knight #185-189, the Riddler is stripped of his deductive powers and left to rot as a member of Gotham City's vast and invisible homeless population.

Having made this connection, the Riddler spends some of his vast fortunes, acquired over many years of crime, to get minor plastic surgery and extensive tattooing, covering most of his torso with his trademark question insignia.

[19] Sometime between this incident and the events of Hush, Riddler was hired to steal artifacts imbued with mystical powers from one of Star City's museums, and then distract the authorities so that the related rituals could be commenced.

However, as a side effect of the ritual performed with the artifacts, the city is plunged into complete darkness, and Green Arrow uses this to his advantage, moving in and apprehending the Riddler.

[20] He is next seen escaping Arkham Asylum during the worldwide supervillain breakout engineered by Alexander Luthor Jr.'s Secret Society of Super Villains days after the prior supernatural disaster.

In Detective Comics #822, the first of a series of issues written by veteran Batman writer Paul Dini, the Riddler returns, having spent much of the previous year in a coma due to brain damage after being struck in the head by Shining Knight.

Bruce suspects foul play, and eventually tracks down the killer, whom Riddler is also close to catching before Nigma is bludgeoned over the head by a shark-tooth club.

The two join forces to defeat Clayface, and after witnessing Mary's new malicious approach to crime-fighting, suggests that she consider finding a mentor to help her control her powers or at the very least get some anger management counseling.

The young man, whose girlfriend was caught in the crossfire of a gunfight between Nigma's gang and security guards, captures Riddler and attempts to kill him, but Batman intervenes just in time and saves his former foe's life.

[26] In the third issue, Riddler attempts to solve a pair of unlikely suicides, the first being the second-best female tennis player in the world, the second an ace race car driver.

The two men are led by a woman going by the moniker Conundrum, and their costumes sport black and green color schemes along with disturbingly familiar question mark emblazoned on their outfits.

After washing up in the men's room, Riddler sees a gossip show on closed-circuit television, showcasing a plainclothes Harley getting into a car with Hush disguised as Bruce Wayne.

[28] In Tony Daniel's "Life After Death", Riddler appears early in the story at a gala party attended by Arkham, Dick Grayson, Huntress, and Oracle, hired by Penguin to find the Black Mask.

Although the Riddler continues to be steps ahead of the Dark Knight, he is eventually defeated by the combined efforts of Batman, Commissioner James Gordon and Wayne Enterprises CEO Lucius Fox.

Alongside the Trickster (whose arm Edward had placed a bomb in), Riddler begins ruthlessly punching and beating the Flash (Barry Allen) before the speedster is quickly rescued by the Pied Piper.

He is first seen in custody at the GCPD, assisting them in solving a variety of crimes, including locating Joker's whereabouts, before stabbing a police officer to death 26 times.

[33] Riddler eventually formed his team, consisting of himself, Poison Ivy, Scarecrow, Deathstroke, Clayface, Killer Croc, Two-Face, Firefly, and Victor Zsasz.

However, Batman's observations note that "[Nigma] exhibits personality disorders consistent with a fanatic narcissist, egocentrism, and megalomania crossed with severe obsessive compulsion".

He is not especially talented in fisticuffs (although his endurance has grown from having to engage in it over the years), but sometimes employs weaponry that exploits his gimmick, such as exploding jigsaw pieces, question-mark-shaped pistols, and his infamous question-mark staff, known to house a wide variety of technological devices and weapons.

His most formidable depictions emphasize his intelligence and cunning, portraying him as one of few rogues capable of seriously taxing Batman's mental prowess, while also willing to take the precaution of obtaining firearms to deal with the superhero.

The latter approach has proved polarizing, with some fans finding it wasteful in light of the character's classic status and history of compelling stories, while others argue that most of his popularity has come from media other than his comic storylines and enjoy the notion of knowing that his "real" threat level is overrated.

In their first encounter, he sets his fellow rogue up with a bomb and sends Batman off chasing riddles that would lead to its defusing, as well as away from his real plan: to steal a vast amount of priceless baseball merchandise.

In the middle of a riot at the police precinct caused by the Riddler, Batman pursues the villain in a car chase and eventually subdues him with Waylon Jones' help.

[48] The Riddler has a heroic counterpart in the antimatter universe called the Quizmaster, who is a member of Lex Luthor's Justice Underground (that Earth's version of the Injustice Gang) which opposes the evil Crime Syndicate of Amerika.

In the course of the series, it is revealed that Enigma seeks this power to save his daughter after she was mortally injured, but the ritual fails when Despero is replaced by one of his henchmen in an attempted coup, creating an imbalance that destabilizes reality until Trinity's allies can regain enough of their own memories to help their loved ones come back to themselves.

Cover of Detective Comics #140 (October 1948), the first appearance of the Riddler. Art by Win Mortimer . (note the Riddler Puzzle trap in this drawing was actually used in an episode of Batman when John Astin guest starred as the Riddler)
Edward as he appears in Joker .