So, on the planet of Episol live the species Episolians. They have conquered and enslaved most of the galaxy, and recently they have laid eyes upon a planet called Earth, with a primitive species they plan on conquering. On stardate 22.34.68 a force of 50,000 Episolians, leaving with 100 gunner ships, 25 battleships and 5 carriers leave to conquer Earth. The send a small scout unit to recon Earth, and when news comes back about Earth, every soldier is terrified.


The scouts, when entering the Sol System, passed 4 gaseous planets before reaching Earth. On the way, when they passed Neptune, they saw a humongous starship twice the size of anything their species ever made. They landed on Earth, with their magnetic proton launchers in paw, and saw the humans for the first time. They were massive behemoths, many times the size of any Episolian. The Episolians were the size of human basketballs, and looked like balls of fur, just like a tribble. When they tried to fight the humans, their weapons caused mere blisters, even the cannons they had only caused sprained ankles and the occasional compound fracture.

An Episolian in Earth gravity weighs up to 2 pounds, and a human infant can crush them easily. The Episolians yelled and screamed at the humans for mercy, as they were being picked up and stroked to death, but the yells of agony just sound like purring and vibrating to the humans. The humans also live for over 1,000 cycles (80y) while Episolians only live 100 (8y).

So my question is, given their shortcomings, how could the aliens conquer humanity?

Details about invasion

From radio reports made by humans, the Episolians decide to invade the most powerful human nations. Those are the USA, USSR and China, along with a small detachment in Europe, mostly the UK and France. They cannot voyage into Siberia, as it is far to cold for them. Water deeper than 8 feet is also a problem if they’re on foot, as well.


closed as primarily opinion-based by Aify, Culyx, JBH, user535733, Andon Jun 29 '18 at 18:51

Many good questions generate some degree of opinion based on expert experience, but answers to this question will tend to be almost entirely based on opinions, rather than facts, references, or specific expertise. If this question can be reworded to fit the rules in the help center, please edit the question.

  • $\begingroup$ Hello, Guy, and welcome to Worldbuilding. This is an interesting question, but in its current state, it is very broad. Perhaps you could edit to focus on one specific aspect of the invasion. Please take our tour and visit our help center to learn more about the site. Have a nice day! $\endgroup$ – Gryphon - Reinstate Monica Jun 29 '18 at 17:08
  • $\begingroup$ Are the rest of the galaxy pathetic weaklings? If not, use the slaves! $\endgroup$ – Callum Bradbury Jun 29 '18 at 17:20
  • $\begingroup$ They weren't that short. $\endgroup$ – Reactgular Jun 29 '18 at 17:22
  • $\begingroup$ I'm voting to close this question as too story based. You're literally asking us to write your story. This is a major plot point involving how you're representing the strengths and weaknesses of two species, therefore it is not about worldbuilding according to our help center. $\endgroup$ – JBH Jun 29 '18 at 18:21
  • $\begingroup$ Ancillary to my answer, I would also like to point out to Guy some major inconsistencies - the Episolians could understand multiple human languages and knew from radio chatter which the strongest nations on Earth were (I'm assuming this is in the 1980s, given the presence of the USSR), and yet they had no idea of human size and strength? No means of communicating? $\endgroup$ – jdunlop Jun 29 '18 at 18:27

Among their other problems, the Episolians are suffering from their author, who in turn is suffering from Sci-Fi Writers Have No Sense of Scale. With 50 000 invaders, size notwithstanding, that's odds of 100 000 to 1, assuming humans haven't achieved even greater population density by the time period of your story. They could kill us all, but they couldn't conquer or enslave us.

That being said:

Kill All Humans Vol. 1 - I Will Throw a Giant Rock At You

The conquering tribbles, horrified at individual humans' ferocity and strength, retreat to their spacecraft. Assuming that the Neptunian spacecraft isn't an indicator that we've achieved industrial capacity in our outer solar system (in which case the Episolians are royally screwed), they have more advanced engines, propellant systems, and interstellar travel. They go to our oh-so-convenient asteroid belt, gather up a few likely rocks, and huck them at Earth, annihilating millions. Earth, cowed, surrenders lest more rocks be hucked at them.

(As mentioned, if we already have sufficient spaceborne capacity, that might not be enough to cow us, and we might try a defense, at which point the question is who can achieve space superiority.)

Kill All Humans Vol. 2 - Fever Dreams

The Episolians, given their tremendous physical fragility, are spectacular biochemists and physicians. Their stealthiest ninja-scout manages to scrape a cell sample from a sleeping human, and returns it to one of the carriers' bio-labs, where a targeted virus is created. It either weakens or kills 95% of the planet's population after the carrier aerosolizes the virus in the atmosphere.

Conquering then becomes substantially easier, though enslaving still remains problematic.

  • 1
    $\begingroup$ I believe the neptunian spaceship is referencing a probe of some sort, probably one we already have out at / past neptune, but I may be wrong $\endgroup$ – Callum Bradbury Jun 29 '18 at 17:34
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    $\begingroup$ I considered that, but even at 2lbs apiece, there's no chance that anything we've put past Neptune is "bigger than any spaceship [they've] ever seen" if they're transporting fifty thousand of their kind over interstellar distances. $\endgroup$ – jdunlop Jun 29 '18 at 17:40
  • $\begingroup$ Of course, the OP could also be off in terms of that scale, too. $\endgroup$ – jdunlop Jun 29 '18 at 17:41
  • $\begingroup$ The Epsilonians can't even knock over a human, how are they going to move an asteroid? I suppose you don't need much impulse to move something in space, but with the minuscule caliber of their energy-imparting devices, it'll take an awfully long time. $\endgroup$ – Nuclear Wang Jun 29 '18 at 18:39
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    $\begingroup$ @NuclearWang They can also move themselves over interstellar distances. It's a major inconsistency, true, but it falls under The Kzinti Lesson. If you've got the ability to move large masses through space (they do), then you have the ability to hurl large masses at planets. $\endgroup$ – jdunlop Jun 29 '18 at 18:56

Well, unlike a previous invasion, where the entire fleet was swallowed by a small dog, this invasion is at least a bit closer in size and scale.

Since direct physical attack is unlikely to work (unless the desired effect is to erase the biosphere, in which case dropping a massive asteroid will work), the invaders need to consider PSYOPS. Humans respond to various messages, and some messages are far more powerful than others. Careful observation from orbit, as well as intercepting communications, radio and television traffic should provide the Episolians with abundant information.

From this mass of information, they then select "target audiences" of people or groups which have the will, resources and ability to carry out whatever plans the Episolians have for Earth. Considering that the Humans and much of the Earthly biosphere seems much larger and more dangerous than anything else in the Galaxy, the preferred Psychological Objective should be to recruit the Earthlings to become the "enforcers" of Episolian rule, and tempt them to accept by offering technology and other incentives to do so. The Aliens will (unless they are really stupid) have fail-safes and dead man devices installed on their technology, and even if Humans rightly suspect these are present, will not be able to decipher and disarm them.

Soon, humanity is busy converting the industrial might of Earth to producing starships, weapons of war and supplying space crews and Marines to man the Armada, all for the greater glory of the Episolians. Given the ferocious race the Episolians have recruited to fight their wars for them, the rest of the galaxy rapidly offers terms to prevent giant Space Marines from putting them in kennels, feeding them tasty treats and throwing sticks for them to retrieve.

Even truly ferocious creatures like the Ravenous Bugblatter Beast of Trall will fall prey to the devious nature of humans, who in addition to massive weapons of destruction also carry towels across the Galaxy....

  • They have superior biological warfare, surely because of their exposure to a myriad alien species. Only humans who submit will get the treatment.
  • The scouts had handheld proton launchers. The shipboard proton launchers of the fighters can handle any human aircraft or tank. The guns on the battleships can decapitate Cheyenne Mountain.
  • Their battleships can easily achieve space superiority.

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