When you have two different comic series telling the same story simultaneously, this is what we call a Crossover. Let’s use the current Justice League series as an example. It did a crossover with the Aquaman series when it told the tale of how Aquaman’s half-brother, Ocean Master, led the army of Atlantis in attacking the surface world. The story was printed in Justice League issues 15 to 17 and Aquaman issues 14 to 16, alternating from one issue to another.
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