>>154103288
Joker replaces all of Gotham's drinkable tap water with ocean water.

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>>154103288
Canonically it's the first thing he does, Batman: The Man Who Laughs from 2005 goes into details.

>>154103288
well the tyrant bruce poisoned the gotham water supply with fear toxins and abused and brainwashed vikki vale. gets very dark if you make everyone there chatbots and toss it together. that bruce is...very quick to cross lines.

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>>154103397
Beat me to it. He attempts to poison the people of Gotham in "The Man Who Laughs" but fails.
The Laughing Fish story also has him dumping into the ocean a chemical that affects all the fish. But instead of poisoning them, his goal is to make them smile.

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>>154103288
He does in the TV series actually. He uses a chemical to make the water turn into an oily gelatin, I think it was called "joker jelly" or some other deadpan name.

>>154103288
In addition to the stories already mentioned, it's what Joker and Scarecrow were trying to do when they teamed up during Knightfall.

>>154103397
>>154103671
Also recreates this crime during Death of The Family, only the spin he puts on it is self sabotaging the resavoir so it can't spread, but still dumps people into the water to match the kill count

>>154103830
Multiple in there, actually. There's another where he laces the water supply with a compound that uses a placebo effect to render people vulnerable to his time-stopping remote.

>>154103288
Well, because poisoning a water supply is the go to of evil villains throughout history.
Even now.
There is a real present existential threat if some nefarious group decides to drop something bad into the water supply of a city or town.
It will go sideways very very fast and very hard. Do you realize how vulnerable yet essential your water supply is?

Yeah, it's bad.
And the 87 movie plot was so fucking on the nose it's almost like they are telling you how bad it is with the various chemicals and "food"s we use every day.

>>154103830
it's gelatin, but it's also a meta-joke about the "polywater gap" that was in the news for most of the late 1960s - polywater was an erroneous discovery of a thick state of water, which the press got wind of and started panicking about, fearing the Soviets would turn the US's water supply to jelly if the US couldn't replicate the polywater process and figure out how to reverse it

eventually - and in spite of real scientists repeatedly saying smart stuff like "it's probably just a mistake" and "if it existed, we'd see polywater in nature, there would be organisms that relied upon it" - the guy who thought he'd discovered it satisfied himself that he couldn't repeat the conditions to create polywater and published a new paper retracting his earlier claim and explaining that he probably just hadn't cleaned some lab equipment properly

polywater also shows up in Star Trek around the same time, and for the same reasons; there were novels and a couple of movies (tv movies I think, maybe a pilot for a show that didn't happen) about the concept, and it ran and ran for years with the press constantly screaming "polywater gap" like it was the scientists who were mentally deficient

>>154103288
in Arkham Asylum he tries to contaminate the water in the Gotham River with Titan

>>154103671
>But instead of poisoning them, his goal is to make them smile.
Because he thinks he can copyright the "Joker Fish" image and make millions, but the copyright office won't let him and so Joker resorts to murdering the bureaucracy to push through the red tape.

>>154103397
/thread