Crisis On Infinite Earths wasn't the first big crossover event in comics, but an argument can be made that it's the best. The writer/artist team of Marv Wolfman and George Pérez, joined by creators like Jerry Ordway and Dick Giordano, crafted a story that ended the DC multiverse, resetting the history of the venerable comic publisher. The battle against the Anti-Monitor has inspired creators for decades, all because of Crisis On Infinite Earths' legendary reputation.
Source:https://www.cbr.com/best-heroes-dc-crisis-on-infinite-earths/