Galactus

Galactus, viewed as the personal embodiment of the Living Force by the Heralds of Galactus, was a monotheistic deity whose worship was promoted by the Hetalds to non-Herald races in missionary activities.

The Inhumans banned the worship of Galactus on planets they controlled, but Galactus worship survived.

As the Kree Empire took over the Milky Way Galaxy, worship of Galactus was mainly subsumed by another monotheistic religion, the worship of the Kree deity the Supreme Intelligence.