It may have been Doomsday that killed Superman, but the United States government proved that they were the Man of Steel's darkest threat of all. In the wake of a Kryptonian resurgence, a dark conspiracy revealed itself and it aimed to take down every Kryptonian, even Superman, for good.
As one of the DC Universe's most powerful heroes, Clark Kent has no short supply of villains who are ready to challenge him. Whether it's the ingenious machinations of Lex Luthor or interdimensional trickery of Mr. Mxyzptlk, Superman has gone up against some pretty devious foes. But it was the infamous villain Doomsday that killed Superman, cementing his place as one of the top enemies in the hero's rogues' gallery. Few enemies have been able to hurt the Man of Steel in the way that Doomsday did, though the sheer force with which the monster defeated Superman brought valuable insight into how the Kryptonian could be taken down.
Related: Superman Lost To Doomsday For One Hilarious Reason
Such information proved invaluable to a clandestine military operation aimed at ensuring that the Earth would be safe from any Kryptonian threat, even the beloved Superman. A deadly conspiracy was uncovered after the Bottle City of Kandor was revived after Geoff Johns and Gary Frank's «Brainiac» story in Action Comics. In Superman's Pal, Jimmy Olsen Special #1 by James Robinson, Jesús Merino, Leno Carvalho, and Steve Scott, the titular hero discovers a trail that leads to the insidious Project 7734, a covert program headed up by General Sam Lane. With thousands of Kryptonians running loose on Earth, Lane drafts Lex Luthor into his operation to come up with defensive and offensive measures against the potential threat they now face. From resurrecting
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