Back when Marvel/DC crossovers were more common, one of Superman's visits to the Marvel Universe saw him receive an incredible power upgrade while interacting with the Fantastic Four and Galactus. Receiving a message suggesting that Galactus was responsible for the destruction of Krypton, Superman embarks on an adventure involving Marvel's First Family, the Cyborg Superman, and the World Devourer himself. However, the crossover event also featured the Power Cosmic, the very same transformative energy source that turned Norrin Radd into Galactus' herald known as the Silver Surfer.
Coming from Dan Jurgens and Art Thibert, 1999's Superman/Fantastic Four was a one-shot issue that saw Superman seeking answers about Galactus and his role in the death of Krypton. Requesting the help of experts on the World Devourer, Superman approaches the Fantastic Four for help. However, things are more than they seem with the arrival of Hank Henshaw's Cyborg Superman. Interestingly enough, Jurgens created Henshaw to serve as a DC villain counterpart to Marvel's Reed Richards, seeing as how Henshaw likewise went up into space in a shuttle hit by radiation. However, the mutations his crew suffered led to their deaths, with Henshaw as the only survivor, eventually becoming the dark Cyborg Superman.
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Sadly, once Superman makes it to the First Family, Ka-El is soon hit by a device created by Galactus, granting the Kryptonian the Power Cosmic itself, and amplifying even his power far beyond the abilities he already has. Having been transformed into the Herald of Steel, Mr. Fantastic confirms in this crossover that Superman has become the "second-most powerful being in existence" with
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