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Alien Species Generator

This is a simple method for creating a randomized alien species to use in your role:playing game. Hopefully you'll come up with something cool! You'll need one 6-sided die or the electronic equivalent.

Part one: Overall Anatomy

Species type

Roll 1D6:

  1. Exoskeletal (Including Insects, arachnids, or crustaceans)
  2. Marine (Including fish or squid)
  3. Scaled (Including lizards or amphibians)
  4. Warm:blooded (Including mammals or birds)
  5. Plant based (Mobile plants like sentient Venus fly traps, walking mushrooms.)
  6. Hybrid (Roll another two times and combine the results!)

Body structure

Roll 1D6:

  1. Long bodied (A body mostly based around the spine, like snakes, caterpillars, centipedes or worms)
  2. Shell:backed (A large amount of natural armour, possibly segmented, Like turtles, pillbugs or armadillos)
  3. Flat bodied (Like some fish or mites. Could also include bat:like beings.)
  4. Insectoid (A separated thorax and abdomen, like most insects.)
  5. Humanoid (A boxy torso, with a conjoined abdomen and all the limbs running directly to the corners.)
  6. Rounded (A rounded body. Might have all of the limbs running from one side (like a squid or jellyfish), but not necessarily.)

Head Type

Roll 1D6:

  • 1 to 2: No head. Sensory organs are based all over the body.
  • 3 to 4: Basically a lump on the body, where two or three of the sensory organs are based in the same place.
  • 5 to 6: A proper head with a neck, containing most of the bodies' sensory organs.

Limb Types

Roll 1D6:

  • 1: No arms or legs. moves like a worm, snake or snail.
  • 2: Legs but no arm s: flexible mouth parts may make up it.
  • 3 to 4: Legs with flexible feet, capable of being used like hands.
  • 5 to 6: Both arms and legs.

Number of Legs

Ignore this if it doesn't have any.

Roll 1D6:

  • 1 to 5: Roll an extra dice, and time the result by two. The result is the number of legs.
  • An odd number of legs. Roll an extra die, and time the result by two, then take away one. The final result is the number of legs (the creature is asymmetrical).

Number of Arms

Ignore this if it doesn't have any.

Roll 1D6:

  • 1: One arm, mounted underneath or as a tail.
  • 2 to 5: Plenty of arms. Roll an extra die, and time the result by two. The result is the number of arms.
  • 6: An odd number of arms. Roll an extra die, and time the result by two, then take away one (the creature is asymmetrical).

Creature size

Roll 1D6:

  • 1 to 2: Small, from 1 to 5 foot tall.
  • 3 to 4: Vaguely human sized, from 5 to 8 ft tall.
  • 5 to 6: Massive compared to humans, around 9 to 15 ft tall.


Roll 1D6:

  • 1 to 4: No wings.
  • 5: Wings instead of arms (None if it doesn't have any.)
  • 6: Folding wings on the back, aswell as arms.


Roll 1D6:

  • 1 to 3: No tail
  • 4 to 5: It has a tail
  • 6: Roll an extra dice: it has that many tails

Part two: Seek, Eat, Procreate

Vision organs

Roll 1D6:

  • 1: It 'sees' by vibration, using antenna, horns or just it's arms and legs (Alternatively, it could hear it's way around with large ears)
  • 2: It 'sees' by taste, using a long tongue or possibly a large nose
  • 3: It has clusters of a great many tiny eyes Roll an extra dice for the number of clusters
  • 4 to 5: It has large, sensitive eyes, complete with eyelids Roll an extra dice for the number of eyes
  • 6: It has extrasensory abilities like heat vision, electromagnetism or even psychic sensitivity

Rolling anything other than 3 to 5 on this chart means the creature has no eyes.

The mouth

Roll 1D6:

  • 1: No jaw. Eats prey by swallowing them whole
  • 2 to 3: A fairly average mouth with teeth, and a single jaw
  • 4: A insectoid mouth with many jaw:like mandibles Roll an extra dice for the exact amount (A roll of one is a beak)
  • 5: Spider-style fangs: punches into the prey, injects venom and then drinks them like soup
  • 6: Strange placement Roll an extra dice (1:3 is on their hands, 4:5 is on their tail), then roll again on this table for type


Roll 1D6:

  • 1: Vegetarian
  • 2 to 3: Omnivore
  • 4 to 5: Carnivore
  • 6: Absorbs energy (Light, heat, electrical, radiation)


Roll 1D6:

  • 1 to 3: Can be either male or female
  • 4 to 5: Asexual
  • 6: Neither, grows by airborne spores

Part three: Environment and Culture


The climate they are used to living in:

Roll 1D6:

  1. Extremely hot, like inside a volcano
  2. Dry and arid, like in a desert
  3. Underground
  4. Hot and humid forests
  5. In swamps, or totally underwater
  6. On or underneath an Arctic tundra

Social structure

Roll 1D6:

  1. Pacifists, who treat each other as equals and try not to disturb the nature around them
  2. True communists, who aren't necessarily violent and at least try to treat each other equally
  3. Patriotic capitalists, who have a monetary system and a military, determined to build a better future for their race
  4. Corrupt capitalists, who lie to their own people to stay in power and generally have large militaries
  5. Monarchists, who have some kind of 'noble' kingship in place, and a big army so that it doesn't get overthrown
  6. A dictatorship or anarchists, controlled by a single person with an iron fist, that are so powerful they don't even have to lie about what they are doing

Technology specialization

Roll 1D6:

  • 1 to 2: The race has access to advanced metallurgy, and uses a great deal of tanks, hydraulics and solid firearms in their armies
  • 3 to 4: The race concentrates on energy manipulation, able to use plasma, radiation and electro:magnetic weapons to great effect
  • 5 to 6: The race has a long background with genetic engineering, using artificial muscles and clones to wage war

Example Species:

Here's an example of a species generated with the preceding tables!

  • Mammal Plant hybrid
  • Insectoid body
  • A proper head with a neck
  • Legs with flexible feet, capable of being used like hands
  • Eight legs
  • Small, from 1 to 5 foot tall
  • No wings
  • It has a tail
  • It 'sees' by taste
  • A fairly average mouth with teeth
  • Carnivore
  • Asexual
  • In swamps, or totally underwater
  • Corrupt capitalists
  • advanced metallurgy

…which could be shoehorned into…

“The Zhll, with strange, furry, three:piece segmented bodies somewhere in between a giant furry ant and a vegetable, are a small but tough species that has a fondness for ballistic firearms: and despite their size, eight multi:use limbs means they can actually pack a lot of firepower at any one time. The freaky, mushroom:like head splits down the middle to show a mouth full of teeth, as well as a long tongue that is used to 'taste' it's way around the swamps that it inhabits. It has a great taste for meat, and is asexual so it can produce very quickly, making it a pest not to be underestimated. What government they do have is controlled from behind the scenes, tricking the easily fooled masses into doing whatever the group leaders seem necessary to keep themselves on top.”


alien_species_generator.txt · Last modified: 2019/11/23 07:26 by wes