Due to the great number of characters involved, several only have silent parts or mere cameos. A number of scenes reference previous films. Most notably Superman's ability to turn back time references " Superman" (1978).
While many of the fights (and carnage) in the film involve characters mostly unrelated, a number reflect the long-time rivalries established in the source comic books. Particularly fitting is Joker being the one to kill Batman, Nightwing killed by Flash (a fellow Titan), Spider-Man taken down by Venom and Cyclops easily taking down both Wolverine and Apocalypse. (Suggesting he was holding back in previous encounters).
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