The origin of the Batman Who Laughs is quite complex. It involves a alternate reality Batman being exposed to a powerful and corrupting force that combined his traits with those of the Joker, creating this sinister character. This transformation led to his malevolent and twisted nature.
The Batman Who Laughs originated from a dark multiverse where a version of Batman was exposed to a toxin that drove him insane and merged with Joker's essence.
The Batman Who Laughs originated in a alternate universe. Here, Batman was subjected to a extreme event that caused him to become a fusion of Batman and the Joker, resulting in his menacing and chaotic presence. This origin story sets the stage for his villainous actions and unique personality.