The eksi are a species of giant isopods that are native to the Abyss. They were observed to consume minerals and initially caused a huge problem for constructions in the Abyss by consuming both building materials and lubricants. After having studied their behaviour they have been domesticated and put to use in Fusion City as waste management and machine maintenance.

Appearance and biology

Eksi are about 20-40 cm long on average and very massive. They weigh, on average, about 4 Kg, but there have been speciments as large as 60 cm weighing up to 7 Kg. They have an exoskeleton that is somewhat pliable, but strong, usually in orange or brown coloration, but it varies a lot between individuals. Eksi are relatively slow for their size, owing to their short legs.

Eksi live by consuming certain mineral compounds, particularly high mass metals, such as iron or complex minerals like veldspar. They've also shown a great preference for degraded lubricant, usually refered to as "sludge", but they don't eat fresh lubricant. The potential use for the creatures became clear.


Eksi were brought back from the Abyss and underwent intense study, primarily by ThalCorp Industries, a company that regularly hires xenobiologists to assist handling local fauna and flora on their offworld bases. Doctor Mia Yol assisted in the study of the Eksi and determined that nothing in their bacterial flora or in their waste posed a threat to Dunian ecology.

Calling the eksi "domesticated" is an overstatement. It's more like a case of them living a good life and society using them for their natural abilities and affinities. Eksi are frequently used for waste clearance since they eat almost everything and are able to break down even hardy metals down to a sludge that can be processed into several raw materials. However, their primary use is for machine maintenance.


All machines require lubricant were moving parts meet in order to prevent heat, parts seizing and excess wear. When lubricant gets warm, it will start to degrade and break down, eventually turning into a sludge that is working the opposite of lubricant, instead causing friction and more heat. This will eventually cause machines to break down unless they are frequently maintained and having the sludge removed and lubricant reapplied.

This is where the eksi come in. They have shown great favor in eating sludge, and their waste has similar properties to lubricant, although it's slightly less effective at preventing heat. But having eksi inside machinery allows them to continually consume degraded lubricant and in turn produce "new" lubricant. This increases the interval between maintenance cycles by an order of magnitude. For this reason, most large machinery in Vault of Life is "infested" by eksi.

Scientific Name
Isopoda Eksalia
40 years
Average Weight
4.5 Kg
Average Length
35 cm
Geographic Distribution
Discovered by

Related Reading

The Abyss
Geographic Location | Jun 17, 2021

The endless, bottom- and surfaceless, vast ocean that encompasses the world. The great, black unknown out there. In a great race to exploit its resources, corporations are sinking a fortune into establish outposts and colonies in the Abyss.

Fusion City
Settlement | Sep 3, 2021

Fusion City is the world's only surviving megacity. A colossal, domed city built in three levels, housing over a hundred million people.

Cover image: by Creative Commons


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Eternal Sage AmélieIS
Amélie I. S. Debruyne
7 Jul, 2021 13:48

Absolutely horrible! Who look at one of those thing and think "oh, why don't we domesticate some, I want my own!" XD Are they absolutely against consuming organic materials?

Feel free to check my ship challenge article.
7 Jul, 2021 14:56

Not at all. Push comes to shove, eksi eat almost everything. Which is why they're so useful for waste-disposal. They're kind of like tiny little "refineries". Or well, not so "tiny", I guess. XD

Author of prize-winning RPG settings Dark Shadows and Cinders of the Cataclysm. Designer of the narratively focused Celenia D10 RPG System.
Eternal Sage AmélieIS
Amélie I. S. Debruyne
7 Jul, 2021 15:21

Even more horrifying! Just the thought of those things swarming nearby would be enough to prevent me from ever sleeping!

Feel free to check my ship challenge article.
3 Aug, 2021 07:53

I really enjoy the note about getting a xenobiologist to confirm that bringing these critters back wouldn't screw with the ecosystem.   These eksi sound insanely useful - what a great find!

Drake's Dozen | Magic and Innovation and Identity, oh my.

3 Aug, 2021 21:30

I think isopods are great and should be used in worldbuilding more. :D I love the idea that they are used for waste management, particularly with degraded lubricant. That seems like it would be quite helpful in a technologically advanced society.

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