Despite being watched over by the Caped Crusader himself, Gotham City is without a doubt one of the worst cities in the DC universe. The city is constantly under attack or being terrorized by one villain or another. The worst culprit of such attacks is the Joker— no one has caused more destruction, mayhem, or terror to the people of Gotham than him.
The Joker continually reigns chaos across the city and kills without thought for the consequence because to him, it is all nothing more than a sick game of cat and mouse with Batman. Gotham City would be a much safer place if Joker didn't use it as his playground.
10 The Massive Gas Attack At Arkham Asylum
The most recent and devastating attack by the Joker is the huge gas attack on Arkham Asylum, labeled A-Day in Gotham City. This massive gas attack killed hundreds of patients and workers alike at the Asylum, including Bane and Jeremiah Arkham.
Even though the attack has Joker's signature written all over it, DC seems to be hinting it might not actually be his fault, but for now the blame lies squarely at his feet.
9 Poisoning All Of Gotham's Makeup & Beauty Products
In Batman '89, The Joker launches a massive campaign against Gotham City that involves poisoning all of Gothams beauty supplies. Whenever someone applies the poison makeup they die with Joker's signature smile stretched across their face.
He is able to hold the whole city hostage by endangering everyone completely at random— and nothing scares the citizens more than the random acts of violence.
8 Bringing Chaos To Gotham In Joker War
Joker War was a huge storyline that devastated the whole of Gotham and knocked Batman down a peg or two. Joker stole all of Bruce's fortune and then released all his toys onto the streets of Gotham. People let their vicious sides out and began to terrorize and destroy their own neighborhoods.
Joker's whole plan was to show Batman that the city is an awful place and no matter what he does they cannot be saved. And in fact, he has made it worse.
7 Joker Randomly Kills Gotham Citizens At Christmas
Starting with the Mayor, Joker started sniping random citizens of Gotham City at Christmas time. This sent the city into a frenzy, with no one feeling safe or knowing who would be the next to drop dead from a sniper's bullet.
Joker then turned himself into the police, but this was only a ruse. People felt safe and rushed to the stores to do Christmas shopping, but that is what he wanted. He planted bombs in the stores as a final bang for the Christmas shoppers.
6 Giving Poison Blood To All The Hospitals In Gotham
In the hit video game Batman: Arkham City, Joker releases his blood to all the hospitals in Gotham. But Joker's blood is poisoned by the toxins he used in Batman: Arkham Asylum.
He intends to let all the people in Gotham die if they use his blood, unless Batman can find a cure. In the third game in the main trilogy, Batman: Arkham Knight, fans discover that people were indeed poisoned and Batman is still trying to cure them before they turn into Joker— much like how Joker has a poison heart that turns whoever kills him into Joker.
5 Joker Turns Gotham Into Zombies In Endgame
Joker enacts his final plan in Batman: Endgame. He releases an airborne flu that makes all people have his signature grin. On top of that, it turns all feelings of love into feelings of intense violence, which incites chaos across the whole city.
The cherry on top of all that is it is spread by laughter, so it quickly spreads across the whole city and Batman is overwhelmed by how to help out the city that he loves so much.
4 Joker's First Appearance In Gotham Incites Fear
When Joker first showed his grinning face in Gotham back in 1940, it was during a set of random killings. Joker would announce who he would kill on television and no matter what protection the people were given he would still kill them somehow.
It sent the city into a frenzy, with no one feeling safe because they never knew who was next to die. And thus began one of the most iconic hero/villain relationships in comic book history, if not pop culture in general.
3 Joker Blows Up A School Out Of Spite
Joker has done a lot of tawful, terrible things, but blowing up a school full of kids is one of the worst. To make matters even worse Joker did it out of spite.
He was mad at another villain, Maxie Zeus, and in order to get back at him he blew up the school. It is a heinous act that the people of Gotham were devastated to see, and was a dark moment even for Joker.
2 Kills Kids Using Cotton Candy At The Fair
During Dark Knight Returns, Joker launches yet another disgusting scheme that involves the harming of children in Gotham. This time the Joker ends up killing a bunch of Boy Scouts by handing out free cotton candy at the fair.
While free cotton candy is great, it's the Joker so of course it's a gift that comes with sinister strings attached: The cotton candy is poisoned, and once again, Joker has the last laugh.
1 The Dark Knight's Joker Caused Random Chaos All Over Gotham
In both one of the best Joker performances and best versions of the Joker of all time, Heath Ledger brings terror to the streets of Gotham as the clown prince of crime in Christopher Nolan's masterpiece, The Dark Knight.
This version of the Joker only lives to cause death and chaos, from blowing up hospitals to pitting convicts and innocent citizens against each other. Joker never stops trying to show Batman the dark side of the people of Gotham, Bruce Wayne included.