In Sci-Fi, there are quite a few 'planet eaters'; giant beings that consume/live off planets or similarly large celestial bodies. The ones I know of are:
- Unicron from Transformers 1986
- Galactus from Marvel Comics (Origin 1966)
- The Blood Moons from Dead Space 3 (First in 2013)
And also possibly Ego the Living Planet (Marvel Comics) (Origin 1966).
I would like to know know what the first instance of a 'planet eater' is in the world of Sci-fi.