Slug (Orphanage)

The Slugs are a hostile alien race that attacked Earth in 2037 and warred with humanity for the next forty years. They are a hive mind consisting entirely of genetically identical individuals; consequently, they are sometimes referred to as a single entity, the Pseudocephalopod.

Anatomy & Physiology
Most Slugs resemble greenish slugs or worms, about five feet long and weighing around 155 pounds. They have no features except for two pale patches of skin on their heads, which serve as infrared-sensitive eyespots. While they have a digestive tract, they do not appear to have a mouth. Slugs manipulate their surroundings with two pseudopods that emerge from near the midpoint of their bodies.

Other Slug variants exist. Planetwide Slug forces are coordinated by Slug Ganglions, which resemble green blobs the size of minivans. These Ganglions transmit messages to and from the central ganglion on the Slug homeworld. The central entity occupies the entire landmass of the homeworld's single continent. It is 8,000 miles long, 4,000 miles wide, and half a mile thick.

Diet
Slugs feed off fertilizers. They directly ingest chemicals such as ammonium nitrate, and their gut contents include ammonia and nitrate compounds. Lacking mouths, it is unclear how they eat, but the circumstances of their "birth" indicate that they may absorb it through their skin.

Reproduction & Life Cycle
The Pseudocephalopod as a whole is immortal, as is its central ganglion on the homeworld. Individual Slugs are created by cloning, and grow rapidly to maturity in vats of aqueous ammonium nitrate. It is unclear how long these Slugs live, but they are treated as highly expendable, suggesting that they are not meant to last.

Homeworld
The Slug homeworld is an unnamed Earth-like planet orbiting a Sun-like star in an unknown part of the Milky Way galaxy. Its atmosphere is colder and thinner than Earth's, averaging 58 degrees Fahrenheit at the equator. Additionally, its atmosphere has less oxygen than Earth's, enough so that a human cannot remain conscious for more than two minutes there. The Pseudocephalopod's central mass covers the entirety of the planet's only continent, and there appears to be no other form of life there. The rest of the surface is covered by ocean.