The Joker is one of the Blind Bag characters in Lego Dimensions 2: The Rise of Enoch, from The Dark Knight franchise.
While very little information regarding the Joker's early life before he turned to a life of crime was confirmed, his true identity remained unsolved for the officials of Gotham City, and despite his capture, no traces could be found on his fingerprints, dental records, and DNA matches against the Gotham City Police Department's databases. The Joker's own testimony, while normally quite true when it came to carrying out threats, seemed at times contradictory, giving conflicting accounts describing past events in his life.
One story that was explained was that during his childhood, his abusive and alcoholic father would often beat his mother in front of him. One night, the father went off crazier than usual and assaulted the mother when she reacted by getting a kitchen knife to defend herself. Angered further by this reaction, the father disarmed her of the knife and attacked her with it, then turned the blade on his son and asked him "Why so serious?", proceeding to slice a single, long gash of scars through each of the little cheeks and leaving him with a Glasgow smile.
Another story he told was that during his early adulthood, his gambling wife told him that he shouldn't worry too much and should smile more often despite the permanent smile his almost-healed scars made. This advice went overhead when she fell into difficulty with loan sharks who eventually carved her face as a retaliation for her lack of payments. Without enough money to afford cosmetic surgeries, she was forced to endure her disfigurement. Her husband didn't care about the scars, and only wanted her to smile again. To show empathy or encourage a feeling of solidarity, he gave his Glasgow smile match hers with a razor, but this instead drove wife into leaving him, unable to tolerate his new appearance. No matter how much he missed, the Joker was driven into madness over the fact that she and the rest of his family and friends couldn't see nor understand his funny side and desires to earn that respect he wanted from the world by upsetting their social order through crime, believing that superficial, meaningless chaos and selfishness was basic human nature.
Eight months before the main plot begins, The Joker was rumored in Gotham to have committed a double homicide and an armed robbery with a "taste of the theatrics", leaving behind a Joker playing card as a calling-card. When given the card by Police Lieutenant James Gordon, Batman promised to investigate, but not before Gordon also warned that just as escalation occurs in terms of the weaponry used by criminals and police, so might the scale and style of criminality change in reaction to Batman's appearance.
Several months later a group of bank robbers, (Grumpy, Happy, Dopey, Chuckles, Bozo and an unnamed bus-driver) under the direction of the Joker, robbed Gotham National Bank which was used as a money-laundering front for Gotham's gangs. The clown mask wearing robbers whittled down their own numbers within minutes in a series of calculated betrayals. Finally only "Bozo" remained, who revealed himself as the Joker to the manager of Gotham National Bank, who had earlier confronted the robbers with a shotgun. The Joker then escaped with the bank's cash in a yellow school bus.
Shortly following the bank robbery, the Joker arrived unannounced at a meeting between the rival mob leaders of Gotham, which he described as a "group therapy session". The Joker proposed that it was Batman's interference that had resulted in idealistic leaders like Harvey Dent rising in popularity, and offered his services to kill "the Batman" for half of all the money that Mr. Lau, an illegitimate Chinese accountant, took away from Gotham for safe keeping. He also warned them that Lau would betray them if arrested, claiming to know a squealer when he sees one. While the Bratva mobster, the Chechen, and Sal Maroni were interested, Gambol, angered by the Joker's lack of respect, put a bounty on him. The Joker later took revenge by killing Gambol and having his men fight for a spot to join the Jokers small gang, made up mostly of violent and mentally-ill escapees of Arkham Asylum, who had been drawn to the Joker as their leader.
Eventually, realizing that Batman had retrieved Lau from Hong Kong and that the police had struck a deal to testify against them, Sal Maroni and the Chechen relented, finally hiring the Joker to kill the Batman. The Joker told all of Gotham that if the Batman didn't unmask himself and turn himself in he would kill innocent people every day. As a result of the Batman not turning himself in, the first major victims were Janet Surillo, the judge presiding over Dent's indictments, and then Commissioner Gillian B. Loeb.
Later, the Joker and his gang stormed a fundraiser at Bruce Wayne's penthouse to kill Harvey Dent and was confronted by Batman. The Joker only managed to escape by throwing Rachel Dawes out a window, who Batman then leapt after and saved.
The killings then continued with two innocents and an attempt on the mayor's life at a memorial for the murdered police commissioner. The Joker appeared in public without makeup, impersonated one of the Honor Guards, and shot his rifle at Mayor Anthony Garcia. Lieutenant James Gordon, however, was killed saving the mayor. As a result of this, Batman told Dent to call a press conference so he could reveal his identity and stop the killings. In a surprise move, Dent instead claimed to be the Batman himself and was subsequently arrested.
While being transported, the Joker and his gang attacked the caravan of police vehicles to kill Dent. Batman soon arrived to stop the assault, but stayed his hand at killing the Joker. The Joker prepared to kill Batman but Gordon - revealed to have faked his death - stepped out of one of the police vehicles and stopped the Joker, and was promoted to Commissioner by the mayor.
With the Joker in custody, Gordon and Batman believed his madness was over, but became alarmed when informed that Harvey Dent had gone missing. Desperate, Gordon let Batman torture the Joker for information, but the Joker seemed unshaken by the pain. Instead, he gleefully told Batman his view of people as selfish and violent, only needing a little pressure before descending to madness. He also admitted he could never kill Batman, considering him his only equal. Dent's kidnapping was part of a test, to see if Batman would save him or Rachel, whom the Joker could tell Batman cared for. The Joker willingly told him where both were located. After most the police were gone, the Joker took his guard hostage and escaped by detonating a phone-activated bomb he surgically planted in the stomach of one the men who was arrested with him, with Lau in tow.
Dent and Rachel each awoke tied to chairs with barrels of explosive material surrounding them and a speakerphone hooked up to the other's location. Rachel confessed her love for him and agreed to marry him. Harvey fell on the floor and his left side was completely immersed in turpentine. Batman arrived, but found Dent instead of Rachel. He realized that the Joker had lied about Rachel and Dent's whereabouts to further crush Batman's morale. Batman rescued Dent as the building exploded and Harvey's face was badly burned, while Gordon was unable to rescue Rachel before the explosion. In the hospital, Harvey was driven to madness over the loss of Rachel, and blamed Batman, Gordon and the Joker. This act caused Sal Maroni to tell Gordon the Joker's location, finding him too dangerous for business. The Joker later met the Chechen in a container ship with Lau and was given his reward: half the mobs smuggled money, which he casually burned along with Lau. He betrayed the Chechen and took control of his men.
The Joker then made a call to a news program where one of Wayne Corps employees was threatening to go public on the news with information about Batman's identity. He was interrupted by the Joker who stated he had changed his mind, believing Gotham to be too boring without Batman. To "give others the fun" he threatened that if someone didn't kill the employee in sixty minutes he would blow up a hospital. Gordon abandoned his ambush on the Joker to focus on evacuating all city hospitals, while, the Joker, poorly disguised as a nurse (still wearing his 'Joker' face paint), entered the hospital room of Harvey Dent. Blaming the mob and Gordon's corrupt cops for the kidnapping and murder of Rachel, he convinced Harvey to exact his revenge upon them. Dent responded by flipping a coin to decide the Joker's fate, giving him the same chance Rachel had. Soon after Dent left, Joker detonated the Gotham General Hospital, skipping merrily away (though pausing and hitting his detonator in frustration when most of the bombs temporarily fail to blow). He and his men then stole one the buses nearby and kidnapped the TV reporter and his crew inside.
While Harvey confronted one of the corrupt cops, the Joker declared that he would rule the streets and that anyone left in Gotham would be subjected to his rule. He told people they could leave now but that he would have a surprise for them in the tunnel and on the bridge, which people then avoided, using instead two ferries, one ship full of ordinary civilians and one of criminals, as Gordon feared the Joker would want to recruit them. However, the Joker had loaded each of them with explosives. In hopes of showing everyone how evil and corrupt they can be he gave the passengers of each ship the detonator to the bombs to the other and offers both survival if they detonate the other ferry. If they didn't choose by midnight, the Joker would blow up both ships.
Batman discovered not only the Joker's location at an unfinished skyscraper, but that the majority of his "gang" were actually hostages wearing clown-masks with unloaded guns taped to their hands and that the people dressed as hostages were the actual criminals. Batman was forced to fight not only the Joker's men but the SWAT teams as well to save the hostages. He finally confronted the Joker, who set several dogs on him and managed to pin him under the scaffolding. He gleefully waited as the ferry's deadline nears, and was visibly disappointed when both ferries refused to kill the other to save themselves. The civilians voted to blow up the other ferry, but could not bring themselves to actually do so, while one of the criminals stepped forward and, taking the detonator, threw it out a porthole saying that the cops should have done that from the start. Before he could detonate both ferries, Batman hit him with his shooting wrist-blades and threw the laughing man over the edge. But, to the Joker's annoyance, Batman refused to kill him, instead grabbing him with his grapple gun and leaving him hanging for the police. With this act, the Joker acknowledged, in a disappointed tone, that Batman really is incorruptible but that Dent is no longer the "White Knight"; he's unleashed the scarred man on the city. Joker states that Dent was his "ace in the hole" in his plan to show the people of Gotham that everyone is corruptible, thus undoing Dent's work before his transformation into Two-Face. Batman left the Joker to dangle helplessly as he was approached by the SWAT team. As they approached him, he laughed maniacally, swaying on the line. Because Joker was able to darken the city's perception of Batman, it can be argued Joker won.
When Bane released the inmates of Blackgate, he also released the inmates of Arkham Asylum. One of the inmates of Arkham remained and wasn't freed by Bane, this inmate was reportedly The Joker.