In Marvel Comics, Galactus is a nigh-omnipotent being who sustains himself on the life energies of the planets he consumes, with the way Galactus goes about devouring his food being a process that most often utilizes a piece of machinery that he builds and operates himself. In a pinch Galactus has an even messier way of eating, giving him multiple options in his pursuit of the perfect morsel of cosmic nourishment.
First appearing as a tool of Galactus’ in 1966’s Fantastic Four #49, by Stan Lee and Jack Kirby, the Elemental Converter allows Galactus to break down a planet’s minerals, atmosphere, and organic material and then transform it into pure energy for Galactus’ taking, leaving a lifeless husk of a world behind.
But in 1983’s Super-Villain Classic #1 and Fantastic Four #257, along with a few other examples, it’s shown that Galactus can consume planets all by himself without the help of the Elemental Converter, showing just how complicated the Devourer of Worlds’ process of eating worlds can be.
Galactus Can Devour Planets Without the Help of the Elemental Converter
The Elemental Converter Is the Easiest Way To Dine on Planets, However
A comparatively more streamlined approach to draining a planet’s life energy, the Elemental Converter is a means to an end that utilizes little to none of Galactus’ vast power reserves. Yet when eating without the help of this specialized piece of equipment, as seen in Super-Villain Classic #1, Galactus pulses with energy as he absorbs and destroys what exists around him, disintegrating his meal almost instantaneously. Meanwhile, Fantastic Four #257 goes a step further by depicting Galactus quite literally descending into a planet’s core to consume the world from the inside out, adding tenfold to the destructivity of this process.

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While Galactus does possess the ability to absorb a planet's energy directly, whenever he tries to, it’s usually a less efficient and more destructive affair, making the Elemental Converter Galactus’ preferred way of eating. Galactus could grow infinitely in size and swallow a planet if he really wanted to, but considering the energy needed to accomplish such a feat and then sustain his new proportions (along with a few limitations on how large Galactus could potentially grow), this would become something that would likely cost more power than what Galactus would get out, making this third technique an improbable option.
Galactus’ Can Build an Elemental Converter From Scratch When Needed
Galactus Could Potentially Use This Piece of Tech (or Not At All) in the MCU
Though the Elemental Converter is an enormous and cumbersome machine for Galactus to be constantly calling from his starship, the Taa II, it’s been seen on multiple occasions in comics that he can simply create one on the spot from all the “dust and soot” in the air, showing not only the extent of Galactus’ primordial power but the technical smarts that come along with constructing one. Of course, instead of ever using the Elemental Converter again, Galactus could always absorb a planet using his inherent cosmic power, ensuring that he’ll never be at a loss when needing a snack.