Galactus

"Galactus, the Devourer of Worlds..."

- The Silver Surfer, The Mazkertis Paradox Chapter 12: Breakout

Galactus is an incredibly powerful entity that consumes planets in order to sustain its own existence. So far, it has only been mentioned in passing.

History
At some point in history, Galactus flew towards Norrin Radd's homeworld with the intention of consuming it, but stopped when Radd confronted it on behalf of his people and begged it not to. Galactus offered Radd a choice: if he chose to become one of its heralds and led it to new, energy-rich worlds to consume, it would spare Radd's world from its hunger. Radd agreed, so Galactus transformed Radd into the Silver Surfer to carry out his new task.

In 150,084 CMT, the Silver Surfer selected JL-511 as a suitable planet to feed to Galactus, but found that it had already been eaten by Garfielf when he got there. The Silver-Silver demanded Garfielf to declare his power in the name of Galactus; unfortunately, Garfielf chose to do this by swallowing the Surfer whole.