"Crisis on Infinite Earths" is a major crossover event in the DC Comics universe that was published in 1985-1986. It was created by writer Marv Wolfman and artist George Pérez and aimed to simplify the complex multiverse of DC by merging various parallel universes into a single universe. The storyline features a powerful being known as the Anti-Monitor, who seeks to destroy all realities, leading to a battle involving numerous superheroes and villains. The event significantly impacted the DC universe, resulting in the deaths of several key characters, including Supergirl and The Flash. It also introduced new continuity, reshaping the histories of many characters and establishing a more cohesive narrative. "Crisis on Infinite Earths" is considered a landmark moment in comic book history, influencing future crossover events and adaptations in other media.