When you think of great Batman villains you think of the insanity of the Joker, the raw fear evoked by The Scarecrow, or the brute strength of Bane... but what about The Riddler? Don't count out Edward Nygma just yet. Ed is one of the few people that can accurately claim they've outsmarted Batman and lived to tell the tale.  He's even taken on other heroes and made them wish they never crossed paths with the man in the question mark cap.

RELATED: The 15 Most SADISTIC Things Reverse-Flash Has EVER Done

Riddle me this: Take off my skin - I won't cry, but you will! What am I? Unlike other Batman villains, The Riddler wants to get caught. He leaves clues for Batman to find out if he can truly be outsmarted. He won't be taking Batman in a fist-fight anytime soon but when it comes to mind games Nygma is always ready and willing to play. The Riddler is not only a formidable foe for the Dark Knight but he's also a cruel one as well. He's tortured innocent victims, shut down Gotham, and even murdered his own daughter. We at CBR look at the 15 most sadistic things The Riddler has ever done. Oh, and the answer is: an onion.

15 TORTURED PEOPLE ON A BUS BY ASKING THEM RIDDLES

Riddler vs Question

Riddle me this: What is the longest word in the dictionary?

Tricky riddles can make us feel embarrassed or dumb if we don't answer them correctly, but what if getting the answer right was a matter of life or death?

The Riddler took a break from tormenting Batman and appeared in The Question comic book. After a conversation he has with a prostitute, he hijacks a bus to prove how much of a villain he truly is. He asked the passengers on the bus a series of riddles and those that get the answers wrong are unfortunately killed. The Question is able to beat the Riddler by asking him philosophical riddles. The Riddler beaten by someone named The Question: isn't that ironic?

Answer: Smiles (between each "s" is a mile)

14 FORCED SEVERAL CELEBRITIES TO KILL THEMSELVES

Riddler Running Underground Game Show

Riddle me this: What crime, if it is attempted, is punishable but if it is committed is not punishable?

If you thought TMZ was bad for digging up dirt on unsuspecting celebrities, wait until you hear what The Riddler did in his one-shot comic book entitled "Riddler and the Riddle Factory." The Riddler became the host of an underground game show that dug up scandals, rumors, and dirt on celebrities. The stories that he came up with were so humiliating that some people wind up committing suicide as opposed to living with the disgrace.

The Riddler had no aspirations of being a host; it was a smokescreen to cover another criminal activity he was pursuing involving the lost treasures of "Scarface" Scarelli. If being a criminal doesn't work out, maybe he can continue with his hosting gig.

Answer: Suicide.

13 PUT AN ATOMIC BOMB IN A STADIUM

Riddler Bombs

Riddle me this: Two baseball teams played a game. One team won but no man touched base. How could that be?

The Riddler loves tormenting Batman, but also proved to be an equally annoying (and dangerous) adversary to a slew of other DC Comics heroes (and sometimes villains). The Riddler temporarily left Gotham City and took a trip to Green Arrow's home turf in order to steal mystical artifacts from one of Star City's museums. Green Arrow tried to stop him, but the tables were turned when the Riddler revealed he had planted an atomic bomb in Star City Rockets Stadium. An atomic bomb? Talk about hating a rival team! I guess the best kind of kill for the Riddler is an overkill!

Answer: They were all-girl teams.

12 FLOODED GOTHAM

Riddler Zero Year

Riddle me this: What runs but never gets tired?

DC Comics rebooted all of their titles with the New 52 back in 2011. Batman's origin was retold in a series called "Zero Year." In this year-long story arc, the very first costumed villain to face off against Batman was the Riddler. Although the Riddler starts out in Arkham Asylum, he eventually escaped and teams up with a villain named Doctor Death to gain control of Gotham. Batman is able to confront Dr. Death and defeats him on his airship, but he is unable to stop the Riddler from blowing up Gotham City's reservoir, flooding the city. The next time you want to call the Riddler's bluff, Batman, we suggest that you don't.

Answer: Water from a tap.

11 DRUGGED BARBARA GORDON AND MANIPULATED HER ACTIONS

Barbara Gordon

Riddle me this: What is something one person can't own but two people can share?

If you think the Riddler is maniacal, check him out in alternate universes. In the DC Comics Elseworlds series "Thrillkiller," The Riddler is a psychiatrist and one of his patients is none other than Barbara Gordon. If it sounds like it has the potential to lead to something awful, then it's because you're absolutely correct. Instead of helping her, the good Doctor keeps her under his control by keeping her drugged against her will. Besides giving her higher and higher doses of valium, he also manipulated Barbara into interacting with people she hated. If not for the intervention of her father and her Butler, Alfred, things could have really taken a turn for the deadly.

Answer: Friendship.

10 FRAMED JIM GORDON

Gotham Jim Gordon

Riddle me this: Why is it a criminal offense for a man living in Chelsea to be buried in Manchester?

The television series Gotham gives audiences a glimpse into the origins of the heroes and villains in the Batman universe. We see a young Bruce Wayne struggling to recover after the murder of his parents. We see the beginnings of Jim Gordon's police career, and we also follow Edward "Ed" Nygma, a forensic scientist for the Gotham City Police Department. At the end of season one it is revealed how unstable he is when we see him having an argument with himself after killing a man. We also get a glimpse into how sadistic he is when he frames Jim Gordon for a murder that Nygma actually committed. Although Gordon's good name is cleared and Nygma is placed in Arkham Asylum.

Answer: The man is still living.

9 CHOKED HIS GIRLFRIEND TO DEATH

Riddler Gotham

Riddle me this: If two snakes marry, what will their towels say?

On the television series Gotham, the origins of The Riddler are explored. Edward Nygma is romantically interested in Kristen Kringle, the records keeper at the Gotham City Police Department. Although she has a boyfriend, we find out that he is abusive of her, so Nygma murders him without anyone knowing. Nygma later won her over with his charms, as she was quite fond of his quirky personality. Kristen told Nygma she was afraid of her ex-boyfriend returning, so Nygma tells her that he killed him. She panics and, while covering her mouth so he can explain to her why he killed him, has found that he has suffocated her to death. Wait a second, he choked Kris Kringle to death? Now that's sadistic, even for you, Riddler.

Answer: Hiss and hers.

8 TRAPPED JIM GORDON AND BATMAN IN A VIRTUAL REALITY MAZE

BTAS Riddler

Riddle me this: What do you call a nurse that treats websites?

In Batman: The Animated Series, Edward Nygma is a software designer that becomes the Riddler after being fired by his greedy employer. It's an interesting version of the Riddler due to his genius being channeled not only through riddles, but also through an expertise in computers. His skill is so amazing that in the episode "What Is Reality?" he's able to put Commissioner Gordon in a virtual reality trap. Even though it's a simulation, The Riddler tells Batman that the experiences that Gordon is going through feels so real that the Commissioner will have a heart attack in less than an hour. Batman is forced to enter the same world and not only was Batman come out on top, but also Riddler is trapped in the very virtual reality maze he created.

Answer: A URLologist.

7 TURNED A FORMER VICTIM INTO A SERIAL KILLER

Riddler attacking woman

Riddle me this: The man who invented it doesn't want it. The man who bought it doesn't need it. The man who needs it doesn't know it.  What is it?

At one point, The Riddler actually operated as a hero and not a villain after suffering brain trauma. He had all of his intellect and genius, but decided to take his skills and become a detective. In the DC Comics series "Countdown To Final Crisis," Riddler is searching for a serial killer. He is eventually kidnapped by the killer and his origins are revealed: when The Riddler was a criminal, his gang was in a gunfight with a group of security guards and a young woman was killed in the shootout. The serial killer was her boyfriend, and her death drove him to become a murderer. Instead of turning him into a hero (like Batman) it made him a murderer. Way to go, Edward.

Answer: A coffin.

6 USED CLAYFACE TO TORMENT BATMAN ABOUT ROBIN'S DEATH

Batman and Jason Todd

Riddle me this: I was carried into a dark room and set on fire, then I started to weep. What am I?

The Riddler was suffering from cancer, and was able to rid himself of it by using one of Ra's al Ghul's Lazarus Pits. The Pit made the Riddler even more psychotic, but during this time, he was able to deduce that Batman was in fact Bruce Wayne, which also meant that Jason Todd ,when he was alive, was Batman's sidekick, Robin. During the storyline "Hush," Thomas Elliot was plotting the downfall of childhood friend Bruce Wayne. The Riddler plotted with Elliot to bring about Bruce Wayne's downfall. To torment Batman, Riddler had Clayface take the form of Jason Todd to make Batman relive Robin's death. Now that's sadistic.

Answer: A candle.

5 GRAVELY INJURED ARROW AND ARSENAL

Green Arrow Arsenal

Riddle me this: A woman proves in court that her husband was murdered by her sister, but the judge decides that the sister cannot be punished. Why?

The Riddler has been a thorn in Batman's side for almost his entire crime-fighting career, but Edward Nygma has also taken on other heroes with various degrees of success. During the Batman storyline "No Man's Land," the Riddler attacked Green Arrow in Star City and was defeated. However, the Riddler got his revenge. At a later date, he attacked Green Arrow again as well as Arsenal. He beat Green Arrow (ironically) with a bat and Arsenal's throat was cut almost resulting in his death. The Outsiders came to the rescue, but not before the Riddler escaped. Perhaps you'll think twice before you insult his purple pants...

Answer: The sisters are conjoined twins.

4 STAGED CRIMES TO MAKE HIMSELF LOOK GOOD

Private Inspector Riddler

Riddle me this: Two silk worms were in a race. Who won?

The Riddler for a while was a private eye working and acting as a good guy. While chasing after Catgirl, a bomb goes off and he receives a second serious head trauma (the first one is what made him "good" in the first place). It's this second injury that reverts him back to his villainous ways. In the Batman storyline "Riddle Me This," Riddler teamed up with Batman to solve the murders of a sorcerer named Sebastian Blackspell. Batman deduces that all of it was actually orchestrated by the Riddler. In order to make it look real, The Riddler even went as far as to poison himself with a nearly lethal dose of Joker gas. Jeez, and you thought the Joker was crazy...

Answer: It was a tie.

3 STUCK BATMAN IN A WELL

Drowning Batman

Riddle me this: In a one-story pink house, everything inside was pink. What color were the stairs?

Although many of Batman's villains want to beat the Dark Knight, they also want to prove that they're better than him. The Riddler is always eager to match wits with Batman to see if he can outsmart his traps and riddles. "The Primal Riddle" was a three-part story in Batman: Legends of the Dark Knight. Batman is thrown into a pit filling up with water. The walls are electrically wired (sadistically done by the Riddler) and Batman has to find a way to exit the pit without getting electrocuted or drowning. To the Riddler's dismay, Batman escapes by sabotaging the trap, only making the Riddler more thirsty for vengeance.

Answer: There weren't any stairs; it's a one-story house.

2 FORCED BATMAN TO ELECTROCUTE HIMSELF

Batman Zero Year

Riddle me this: Why did the foolish gardener plant a light bulb?

During the "Savage City" arc of "Batman: Zero Year" The Riddler floods Gotham city by destroying the city's reservoir and, by doing so, takes over all of Gotham. Power is cut to the city and the Riddler tells Batman that energy can be restored, but only by engaging in the Riddler's most cruel and elaborate trap to date: Batman must hook himself up to an electrode and jumpstart Gotham with his own pulse. Although sadistic, there's a poetry to the fact that Gotham owes its life thanks to the strength of Batman's heart. Gotham is back to normal and the Riddler is sent back to Arkham Asylum.

Answer: To grow a power plant.

1 MURDERED HIS OWN DAUGHTER

Riddler Daughter

Riddle me this: If Theresa's daughter is my daughter's mother, what am I to Theresa?

Believe it or not, the Riddler had a daughter that went by the name Enigma, and was a member of Deathstroke's team Titans East. She was also friends with Duela Dent, the daughter of the Joker (although by the name you'd think she'd be Two-Face's kid) and at one point also claimed to be The Riddler's child as well. Enigma and The Riddler are hired by Gilda Dent to recover Two-Face's famous coin from Mario Falcone. Although they succeed, Enigma calls her father a has-been. Riddler asks his daughter: "What's green and purple and bleeds profusely?" This last act takes Enigma's criminal career to a whole new level and makes the Riddler ineligible for Father Of The Year.

Answer: Her daughter.

Are there any sadistic acts by The Riddler that we missed? Tell us in the comments!