The Phalanx are a techno-organic extra-galactic race and cosmic horror element in the fictional universe of Marvel by Marvel Comics. They were the primary antagonists in the X-Men crossover story "The Phalanx Covenant" and the space opera titled "Annihilation: Conquest".
The Phalanx are machines consisting of smaller self-improving and self-replicating machines. It's a techno-organic race, believed to be an unintentional offshoot of the Technarchy. Which has slaughtered 200,000 races and conquered a 100,000 worlds. They infect the inhabitants of a world and feed on the world until there is nothing left. It's a race that has declared its ultimate goal as the consumption of the universe. They nearly conquered the million-world Shi'ar inter-galactic empire and recently conquered and for a period ruled the Kree galactic empire (rulers of the Greater Magellanic Cloud, a dwarf / satellite galaxy of the Milky Way galaxy).
In reality, unknown to most of the races in the cosmos, the Phalanx were built by the Titans, god-like Artificial Intelligences. They were built to consume those cultures which are worthy and add their societal intelligence to theirs, and therefore their masters. The Phalanx need lots of energy to do what they were created for, and therefore convert matter into energy. Cultures that are worthy are therefore absorbed, resulting that the consciousness and history of those worlds live on forever but the planet itself is consumed.