[1] In its first appearance, the Fantastic Four recover the Ultimate Nullifier with help from Uatu the Watcher and threaten to use it on Galactus, forcing him to retreat.
Quasar tries to use it in an attempt to destroy the Magus, who had acquired the collective power of five cosmic cubes and a gauntlet containing five of the six Infinity Gems.
[2][3][7] During the "Original Sin" storyline, an evolved Mindless One obtains the Ultimate Nullifier and uses it to commit suicide despite the Thing trying to talk it down.
[9] The Ultimate Nullifier has been described as "the universe's most devastating weapon", being able to defy the laws of physics by completely erasing objects from existence.
[3][4] In the hands of a being with an extremely powerful mind, the Ultimate Nullifier can destroy entire timelines and universes.
[12][2][3] An alternate universe variant of the Ultimate Nullifier from Earth-9997 appears in Earth X. Thanos uses it to kill Death, leaving those still living unable to die.