Thanos' most famous brush with omnipotence was in Infinity Gauntlet, the comic that became the backbone of the Marvel Cinematic Universe. During the build-up to the Thanos Quest miniseries, Thanos collected the six universe-controlling Infinity Gems (sometimes called the Soul Gems) and placed them together on a metal gauntlet, allowing him to wield their power simultaneously .

The MCU, of course, turned the Infinity Stones from a plot device into a multi-movie MacGuffin quest, giving each individual stone and its powers much more weight. But the ending was the same: Thanos gathered the six and wiped out half of all life, even if he was doing it for cosmic "balance" rather than trying to lure Death with a mass offering on her behalf.

But Victor Von Doom claimed to be a deity in the pages of Marvel Comics when Thanos was just a flash in Mr. Starlin's mind. One of the most famous stories in Stan Lee and Jack Kirby's original Fantastic Four is in issues no. 57-60, when he steals the Power Cosmic from the Silver Surfer and wreaks havoc.

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This was adapted, poorly, into the 2007 film Fantastic Four: Rise of the Silver Surfer. ("Let's all go for a spin!" Doom makes no pun!)

In the original 1984 Secret Wars by Jim Shooter, the Marvel Universe's greatest heroes and villains are brought to Battleworld by a godlike being called the Beyonder, who wishes them to fight for his entertainment. Doom eventually steals the Beyonder's powers and becomes the series' ultimate villain. This story, up to God Emperor Doom, is certainly the basis for 2015's Secret Wars, even if the latter is a lot better.

Prior to the Secret Wars remake, Hickman also explored Doom achieving godhood in his Fantastic Four series. In the epilogue of "FF" #16 (drawn by Steve Epting), Doom claims two Infinity Gauntlets from the destroyed interdimensional "Council of Reeds" and instead builds a "Parliament of Doom" made up of its own variants.

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Fantastic Four #611 (by Hickman and Ryan Stegman) followed up on this. Drawn to the universe where the Gauntlet first originated, Doom finds a void and fills it with creation, explicitly referencing the Book of Genesis. However, Doom's creations topple him. ("Then, on the seventh day, Doom realizes that a mistake has been made. and concludes that ruling as a god was still 'beneath (him).'"