Batman: White Knight stopped with a fist, i.e. Batman's methods. This led him to turn the Joker into a politician, using the character's intelligence and charisma to win the people of Gotham over. DC Comics had no problems with the ideas that Murphy had for the series such as changing the timeline in Batman's history. However, the adult content like nudity and profanity that Murphy had intended to include were not permitted. Murphy revealed that the Joker in "White Knight" has the real name Jack Napier, a callback to Tim Burton's 1989 "Batman" film where the Joker played by Jack Nicholson also shares
Batman: Endgame with Batman. The Joker attacks Gordon, who responds by shooting the Joker dead. While Gordon phones Batman to relay the news, the Joker rises up and incapacitates Gordon. As Batman screams for Gordon, the Joker picks up the phone and responds "Hello, Bruce." Batman finds Gordon dying, with an axe lodged in his chest. Gordon is revealed to be infected, and he suddenly attacks Batman, but is subdued by Alfred's daughter, Julia. With Nightwing's aid, Batman deduces that the Joker is using a serum capable of healing him from fatal damage, and that the virus contains the serum's complete inverse.