In the original Toho movie arcs from the 60s and 70s, MechaGodzilla was build by a race of invading aliens to kill the king of the monsters, who is the only creature that can stop them from taking over the earth. In the 90s-era reboots, "MechaG" was built by the human race to combat the big guy after he destroyed Mogera, our first attempt at a robotic counter-kaiju.
In both cases, the machine is the perfect symbolic counterpart to Godzilla, who is another in a long line of elemental giant beasts from the depths, including Cthulhu, the Kraken, the Leviathan of the Bible, all the way back to Tiamat, if you know your Sumerian mythology.
"Depths," by the way, can refer to the ocean, the subconscious, deep space, or anything similar. This is the formless void, the unknowable chaos that exists outside our ken and which must be vanquished for human society to flourish.
And so, in the earliest recorded creation story, Marduk the creator-god (who represents order) slays Tiamat (who represents chaos), an act that must be honored as part of the annual cycle (or eternal return) to ensure the proper continuation of the universe. Civilization over nature.
The same battle manifests in the Lovecraftian mythos as that between sanity and insanity, and you see echoes in Dr. Jekyll and Mr. Hyde, on which Stan Lee based the Hulk.
My character Kraxus the Destroyer is supposed to evoke, albeit very weakly, those great beasts from the depths. I keep it simple so as not to distract from the action, which is more fun both to read and to write.
The 1998 Hollywood production of Godzilla sucked, frankly, because it ignored the fantastical, mythical elements, which are the core of the character, in favor of a veneer of realism. No depth, mind you. Just a spray-on tan. The creature of that movie is a mutated iguana. No more. No less. And it's destroyed by some F-16s.
In his sixty-year history, the big guy has been both friend and foe, but the best movies--even Godzilla 2000, the first Toho production after the shitty '98 version--portray him as neither hero nor villain. He is a force of nature and just as unpredictable. A hurricane may produce tragic results, but it isn't evil. It isn't out to get you, but it is violent and indomitable. You can't beat it. You can only endure.
Fanboys like me frost our shorts in foam when Godzilla--not good, not evil, just indomitable--is turned against a force that IS evil... such as aliens trying to conquer the earth or some mad scientist's experiment gone awry. Humanity may marvel at our ingenuity when we lure Godzilla into a volcano and bury him, but we're kicking ourselves a few months later when the flying saucer drops King Ghidorah from its belly.
Three-headed space dragon. Aw, fuck.
Lucky for us, not even a volcano can hold back a god, the unconquerable and capricious will of nature manifest on two legs. And breathing nuclear fire.
Alien, meet mother nature's bodyguard.