It figures I'd move on from
Planet Eater to the natural prey/enemy of the Planet Eater.
This concept is rather more variable than the Planet Eater. While there's pretty much only one modus operandi for a Planet Eater, and they always exist in something with science fiction and fantasy elements together, the Living Planet is far more varied.
For instance,
Isaac Asimov's Living Planet was quite simple-a planet where every part of it is at least sort of alive. This is
Gaia from his Foundation series. (It should be noted that the idea is itself an extension of the "
Gaia hypothesis.")
A little more elaborate yet also elegantly simple is
Solaris, a planet that is covered in a single, huge organism that is capable of forming complex structures and reading minds. (Oops, I guess that's a spoiler. Not that I care.)
From these relatively innocuous "individuals," the Living Planet category then jumps to considerably more formidable beings.
Ego the Living Planet.
Mogo the Green Lantern. (Perhaps closer in class to Gaia and Solaris, but he's still a frikkin' Green Lantern, and they're powerful enough. And he's the one what controls where the orphaned power rings go.)
Unicron. (Unicron is pretty versatile.)
Primus. (Only
often a planet, but "often" is enough.)
Zonama Sekot. (A list of Living Planets that is not particularly complete [partly because
it doesn't provide enough links to the stuff it lists] can be found
here. I've hardly heard of all the ones on the list, but they can hardly be all of the ones out there. Heck, I can name at least three off the top of my head-as I understand, "
Mangaverse"
Galactus was at least sort of a planet, and another Planet Eater, the
Beast Planet, also qualifies. The last is the epically named "
D'vouran," a much less well-known Living Planet from the Star Wars universe, who as its name vaguely suggests eats most of its would-be inhabitants, allowing only its parasitic "natives" to survive, so that they can maintain the thriving tourist towns. Gives a whole new meaning to "tourist trap," doesn't it?) Each of these beings is either a "god" or very godlike.
Out of the latter group of Living Planets,
any of them can traverse deep space as fast as any fictional spacecraft, and
any of them could probably or definitely destroy another planet. Living Planets seem to be a vital part of any science fictional/fantastical space ecosystem, and they're
rarely prey animals.
As with the Planet Eater, the lasting popularity of the Living Planet seems to be because it is iconic, dramatic, impressive, and simple to conceive ideas for.
It's also likely to give those with overactive imaginations nightmares. Watch your step.
-Signing off.
Actually, I'm not quite sure why "unicorn men" aren't a little more common. (Sparklelord from Dr. McNinja is the only other one I can think of, and they didn't actually call him a unicorn man, just a unicorn. And of course, in his non-flashback appearances, he was a motorcycle, but that's not the point.)
