Pre-Crisis (sep 2, 1961 – apr 1, 1985)

Description:

After the discovery of the Multiverse by The Flashes of Earth-1 and Earth-2, the heroes of both Earths, as well as others, would have a variety of crossovers, team-ups, and conflicts across time, space, and the Multiverse. Such crossovers between two or more parallel Earths were dubbed as Crises, and the earliest ones during this era include the first interactions between the Justice League of Earth-1 and the Justice Society of Earth-2, the conflict between the two teams and the Crime Syndicate of Earth-3, their meeting of the Freedom Fighters of Earth-X, as well as Captain Marvel and the Marvel Family of Earth-S, their alliance with the Legion of Superheroes from the 30th Century, their involvement in the eternal war between the New Gods of New Genesis and Darkseid's forces on Apokolips, and many others.

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