Imperiux & Mageddon vs. Marvel Earth

weapon used by the fantastic 4 in their first encounter with galactus to defeat him (not sure if they used it or threated its use)

"ultimate nullifier"

It's a GUn that can distory the universe , so Imperiux & Mageddon will be vaporize with the rest of the galaxy/universe.

From what i heard it can easily distroy a galaxy , but i also heard it full power can distroy the universe as well.

no they did not use it.