Joker was given a nuclear device by Lex Luthor of his world with the intention of destroying Metropolis. He had intended to be far from the city when it detonated, but when Batman arrives to try and stop him, he attempts to activate the bomb prematurely. However, he, Batman and several other members of the Justice League are teleported an alternate world. Joker attempts to take Batman down when his back is turned, but is defeated. Many soldiers from Superman's Regime arrive to apprehend Batman, thinking him to be the Batman native to their reality. Bruce escapes with a high-pitched sound modulator and smoke devices, which also provides Joker an opportunity to escape.
He later appears in Gotham City outside the base of the Joker Clan. The alternate Batman attempts to attack him, but is defeated by the Joker. Yellow Lantern and Hawkgirl appear shortly thereafter to arrest Batman, thinking him to be their Batman. Harley Quinn shows up and confronts the Joker, thinking him to be an imposter of the Joker native to her reality. When he defeats her, Harley realizes that this Joker is not her Joker, but a Joker nonetheless. She invites him inside the Joker Clan building.
The clown gives a speech about Superman's reign over this world and details the 5-U-93-R pill that Superman and Batman have access to. Joker reveals he had gotten one and ingests it; he then suggests they elevate the status of the Joker Clan and become much more than they are. After much applause, a swarm of Regime soldiers infiltrate the base and attack many members of the clan. Joker receives significant gunfire but remains alive due to the effects of the pill. He confronts Hawkgirl and Nightwing before Batman and the Insurgents, consisting of members of the Justice League native to his world, appear and repel the Regime. The Insurgent Batman later takes Joker to Arkham in order to keep him out of the way.
Harley Quinn later breaks the Joker out of prison and proceeds to commandeer a tank in Metropolis. When he and Harley come across Lex Luthor in the city, Joker orders Harley to fight him for his exo-suit. She is defeated, and the Joker proceeds to kill her but is stopped by Luthor.
After the Regime Superman is taken down, Harley escorts Joker at gunpoint back to his world.
Possible Post-Regime Epilogue
Though he had failed to elevate the Joker Clan's status, Joker was convinced a similar organization could be successful in his dimension.
Joker used a series of devastating terrorist attacks to frighten the populace, the convinced the more gullible among them that he was the path to security. The new Joker Clan soon had millions of member worldwide and committed regular anti-government attacks, wreaking havoc on the global economy.
Powers and Abilities
- Genius Level Intellect
- Hand-to-Hand Combat (Advanced): Joker shows that he can handle well in a fight, although using weapons to his advantage. When enhanced by a 5-U-93-R Pill, he was capable of defeating Hawkgirl and Nightwing whom ingested the same substance, each in one-on-one combat. 
- Mechanical Engineering
- Throwing: Joker is a master at throwing playing cards. He can easily hit a target from far away.
- Joker Gas: Joker has canisters of Joker Gas he holds on to. He either hits his enemies with the actual canister as a melee weapon or he can roll them for a long distanced attack.
- Joker Teeth: The madman keeps a collection of Joker Teeth at his disposal that he throws at his opponent's' feet.
- Joker has six available costumes.
- Joker was voiced by Richard Epcar.
- 12 Appearances of Joker (Injustice: Earth One)
- 10 Images featuring Joker (Injustice: Earth One)
- 3 Quotations by or about Joker (Injustice: Earth One)
- Character Gallery: Joker (Injustice: Earth One)
- Joker at the Injustice: Gods Among Us Wikia.
This character is or was primarily an enemy of the Justice League, in any of its various incarnations. This template will categorize articles that include it into the category "Justice League Villains."