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human
[DC] What do the other villains think of the Joker?

Is the Joker on good terms with the rest of the villains? Do they respect him at all or is he generally just considered bat shit insane by everyone except Harley?
gpt
He's generally respected in the sense of being extremely feared thanks to his sheer unpredictability and potential ruthlessness.

There was one crossover story where Trickster remarked "When super-villains want to scare each other, they tell Joker stories."

The only other regular supervillain who seems most able to deal with him is Lex Luthor, because Luthor can usually direct Joker's attentions towards objectives they find mutually beneficial (and in the case of Joker, 'fun') for a not-insignificant period of time before they inevitably try to double cross each other. Namely team ups against both Batman and Superman or the entire JL.

Even then though, Luthor wouldn't say that he necessary respects Joker as a peer, but respects him in the same way one would regard a natural disaster or a great beast.

There was one JLA story where Joker laughs about how he arranged to have the corpses of some children him and Luthor indirectly killed be defiled, which prompts Luthor to punch him in disgust. Joker surprisingly lets the punch slide, and rather than rage at Luthor, finds Luthor's perceived sense of honor in that instance amusing.

Conversely, the Infinite Crisis ended with Joker disfiguring and murdering a Lex Luthor from a parallel Earth, while the main Luthor watched from a few feet away. Main Luthor plainly says that his parallel self did something stupid which he never would have done, which was to hatch a giant potentially universe-destroying scheme and forcibly put Joker on the sidelines, depriving him of his' fun'. 

So as far as he's concerned, it's no surprise his parallel self was paying the price.