History (Submitted by Oracle)

The Joker: 2001 - 2004

It is difficult to know where to begin with this criminal. The Joker is, without a doubt, Batman's deadliest foe. We don’t know where he came from exactly or why he is so deranged, but he has forever tarnished the reputation of our great city with his foul presence. We are not even certain the Joker knows where he came from. We have no less than thirty accounts of his “backstory” on file, all given by the Joker himself and all different, though the punchline of it all boiling down to “one bad day” seems to be consistent, and has even become something of his personal mantra, as he believes quite fervently that anyone can be brought to their lowest point with just one bad day.

We saw evidence of this in our first encounter with him, when the Joker killed dozens during a bank robbery just so that he could get arrested. Once in jail, he promptly escaped, but not before giving notorious mob boss Sal Maroni a vial of acid to splash on the face of Gotham’s favorite son, District Attorney Harvey Dent. All it took to turn the White Knight of Gotham into the deranged killer Two-Face was that one bad day, much to Joker’s glee. Armed with this proof of his theory, Joker would unleash a reign of terror for the next several years.

In this crime spree, Joker pushed the limits of Batman’s code time and time again. Joker stressed that Batman could put to it all he would just forget the code and kill him, even setting up nearly foolproof devices for his own execution that only relied Batman to pull a lever or push a button, but still Batman kept to his code and continued to drag Joker back to Arkham. Though Joker claims to like it in Arkham, he continually escapes almost effortlessly, demonstrating his almost paranormal criminal genius. He even escaped once just to see a matinee showing of “Blazing Saddles” before he had returned to his cell while authorities were still in the midst of their manhunt, because he thought it to be a “hoot”.

Of course, this was just the beginning of the Joker’s reign, his greatest attempts to break the bat were yet to come.[1]

The Joker: 2004 - Present

In August of 2004, Joker escaped from Arkham Asylum. It was nothing out of the ordinary for him. In fact, he had escaped once or twice earlier that month and had accomplished little in regards to criminal activity each time. But most of his work had been behind the scenes, setting his plans in motion for his next experiment in testing his “one bad day” hypothesis. Having failed to get under Batman’s skin, except for when he played a part in Dent’s transformation into the criminal Two-Face, Joker realized that the best way to get to Batman was through his allies. Since he had no ideas to the real identities of Robin and Batgirl, Joker realized that my dad's weakness was not by coming at him directly. No, Joker focused on his family.

So in an attempt to give my dad one bad day, Joker would give my mother, myself, and my brother our own “one bad day”, all at once. Joker succeeded in two-thirds of his plan, giving my mother a harrowing experience that left her with PTSD, crippling me, and almost forcing my brother to kill Batman to save his own father, but when the moment of truth came and Batman had the chance to kill the Joker, Batman proved the stronger person by not giving in to the perverse clown’s plot and instead only busted the Joker’s jaw to get him to shut up for once. However, Joker’s plan did result in the destruction of the Dynamic Duo with Robin so thirsty for the Joker’s blood that he could no longer hold respect for Batman or his code.

Later, Joker would follow this up when he broke off his profitable partnership with Ra's al Ghul in order to deviate from the League of Assassins’ plans to broadcast the torture and murder of Batman’s second Robin, Jason Todd, over the internet. Still, even that would not be enough to drive Batman to kill him, only furthering Joker’s descent into a maniacal obsession with the Caped Crusader that remains to this day. This was the second time Joker had unintentionally put me on a path to becoming Oracle. So guess what, Joker… the (expletive) joke’s on you![2]

Threat Assessment


  • Criminal Mastermind
  • Chemical Weapons Expert
  • Insane Beyond All Hope
  • Remarkable Strategist and Tactician
  • Expert Brawler
  • Creator of the Lethal "Joker Venom" Toxin
  • Access to a Variety of "Deadly Gag" Weaponry
  • "Joker Venom" Toxin


Missing Data


Missing Data

Arkham Files

Medical Profile

  • Patient is in excellent physical health despite his skin having been irreversibly bleached white and hair turned green after being exposed to a vat of chemicals.

Psychological Profile

  • Patient’s wide array of mental illnesses is difficult to diagnose.
  • Patient is a homicidal psychopath with a total disregard for human life.
  • Patient is obsessed with the Batman.
  • Patient is a pathological liar, often telling contradictory stories about his past.
  • Patient has a bizarre, macabre sense of humor.

Behavior Profile

  • Patient gained considerable following among the other patients, including ex-Arkham staff psychiatrist Harleen Quinzel (Patient #99312).
  • Patient is EXTREMELY dangerous… Patient has killed dozens of people, crippled Police Commissioner Gordon’s daughter, taken responsibility for several acts of terrorism, and violently killed one of the Batman’s young vigilante protégés.
  • Patient does not like to be called the “Clown Prince of Crime”.
  • Patient is a talented chemical engineer. His person and cell require frequent searches to be certain he has not acquired any chemical contraband which could be used to create his lethal signature weapon, “Joker Venom”
  • CAUTION: If patient offers to do a magic trick, call for security immediately.
  • Threat Assignment: Severe
  • Treatment Ranking: 6-Hostile
  • Intake Interviewer: Dr. Roy Westerman
  • Assigned Patient Coordinator: Dr. Byron Meredith[3]

Trivia and Notes


  • Joker's mind is so chaotic telepaths avoid him. Sam Simeon became insane after looking into his mind.
  • He seems to have a certain fondness for Vicki Vale and has never intentionally hurt her, even going so far as to shoot one of his men who bruised her face while kidnapping her. Also, while incarcerated at Arkham, Joker writes letters to Vicki. She passes them off to Bruce for analysis into Joker's psychological state. They are, surprisingly, not that deranged and seem actually quite mundane.[4]
  • He broke out five children from a Cadmus facility and formed the Royal Flush Gang. He used to be their leader.
  • His criminal activity falls under ARGUS jurisdiction.
  • When he's in Arkham he's housed in the Solitary Confinement.
  • It is possible Joker was the leader of the Red Hood Gang who fell into a vat of acid.
  • He's a mentor of Dee Dee[5], Dottie[6], Yo-Yo and Bianca Steeplechase.[7]


  • Joker's Patient number (#42540) is a nod to his first comic book appearance: Batman #1, April 4th, 1940.
  • "The magic trick" is a reference to the Dark Knight movie.
  • Dislike to the name “Clown Prince of Crime” comes from Gotham City Sirens comics.
  • The Jack Napier alias is a nod to the 1989 Batman movie.
  • Joker forming the Royal Flush Gang is a nod to the Justice League animated series.

Links and References

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