Benjamin Grimm, the Thing, has faced many powerful villains in his career as a hero, and he went toe to toe many times with Doctor Doom, the recurring nemesis of the Fantastic Four. As an experienced fighter, Ben emerged victorious from many confrontations, but Marvel fans could never imagine that his most embarrassing defeat came not from the Latverian tyrant, but from his mom.
After gaining absolute power, saving what was left of the Multiverse after the Beyonders' Incursions, creating and ruling Battleworld as the God-Emperor Doom, and then losing everything to Reed Richards once again, Doom realized that seeking power for selfish reasons could not be his true calling. He decided to try «the other way» and become a hero, taking the place of the recently deceased Tony Stark as the Infamous Iron Man. Doom's attempt at righteousness and altruism was hindered by his supposedly dead mother, Cynthia. When Ben Grimm, working for S.H.I.E.L.D., tried to track down Doom in Latveria (in Infamous Iron Man #3, by Brian Michael Bendis, Alex Maalex, and Brian Hollingsworth), he was confronted in the ruins of Doom's castle by Cynthia, who called him a "naughty boy" for harassing her son for all these years.
Related: Fantastic Four's Thing Is Dating a Supreme Being Greater Than Galactus
Cynthia von Doom was once a Romani sorceress who died after making a deal with Mephisto, thus relinquishing her soul to the powerful demon. Doom's main purpose for the first part of his life was to find a way to free his mother's soul, and he finally did it with the help of Doctor Strange in Doctor Strange and Doctor Doom: Triumph and Torment (by Roger Stern, Mike Mignola, and Mark Badger). Cynthia was supposedly in Heaven, so her sudden reappearance
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