Endless Space – Imperium Aeterna Mod

We’ve put quite a number of hours into Endless Space here in the team at Mana Pool and during this we’ve ran into plenty of things we’d like to tweak or see done in a slightly different way. The Endless Space developers have been so kind as to support modding in an active and extremely helpful manner, which just begged to be used. As a result, we present Imperium Aeterna – which roughly translates to ‘Eternal Empire’.

Our goal is to maintain the vanilla ‘experience’ as much as possible, but to enhance our enjoyment of the game with enhancements and tweaks over time. This mod will grow as we gain ideas and or incorporate other mods and could become as little or as large as necessary to enjoy the game to the fullest.

Anyone is free to download, play and use the contents of this mod in their own mods – provided that full credits are given accordingly and a link to this page is added.

Imperium Aeterna Mod

>> Download <<

This mods adds and changes the following in your Endless Space game

  • A new Tech Tree, adding 5 new Technologies which each unlock a new System Improvement.
  • An overhaul of the Combat Modules, which adds more depth to ship design.
  • A Combat Overhaul, removing the vanilla Long/Medium/Short range mechanics and replacing it with a more logical Heavy/Normal/Light set of variants for each weapon.
  • Reworked the Ship Classes, so there are now 5 distinct classes instead of minor variations.
  • Added ship defense bonuses to Engine Modules – No longer included: Developers added evasion to engines in Vanilla.
  • Planet Creation, a new technology near the bottom of the Expansion tree which enables you to terraform Asteroids into Barren planets.
  • Planet Size Terraforming, new technologies which enable you to increase the size of planets.
  • Gaia Planets and Gaia Terraformation.
  • 62 New Anomalies (116 total) and 4 Tiers of Anomaly Reductions.
  • A new unique planet “Aeterna”, with its own Wonder, Temple and Events.
  • An overhaul of the Diplomatic AI.
  • Coloured Anomalies – No longer included: Developers added this in Vanilla.
  • Coloured Planet Types – making it much easier to distinguish between the different tiers.
  • Coloured Exploitations – making it easier to distinguish between exploitation types.

Click any of the screen shots for a larger version.

  • New Anomaly
  • New Anomalies
  • Orbital Tech Tree Icons
  • Aeterna
  • Aeterna
  • Aeterna Event
  • Tiny Planet Expansion


Installation Instructions

(Windows 7 – for any other OS, find the equivalent folder where your Endless Space user data is stored.)

  1. Download the latest version of Imperium Aeterna at the end of this article.
  2. Extract the Archive. (Download 7-Zip for free)
  3. Goto: C:Users\Your User Name\Documents\Endless Space\Disharmony
  4. Create a folder named “Modding
    C:Users\Your User Name\Documents\Endless Space\Disharmony\Modding
  5. Place the entire ImperiumAeterna folder there.
    C:Users\Your User Name\Documents\Endless Space\Disharmony\Modding\ImperiumAeterna
    C:Users\Your User Name\Documents\Endless Space\Disharmony\Modding\ImperiumAeterna\Index.xml
    C:Users\Your User Name\Documents\Endless Space\Disharmony\Modding\ImperiumAeterna\Folders
  6. In Game – Go to “Mods” and select Imperium Aeterna.

When you re-launch Endless Space, the bottom left of the title screen of the game should show you the version of Endless Space you are running, with the version of the Mod right below it. Have fun!


Updating to a New Version

Updating is extremely straight forward, but here are explicit instructions for those who asked

  1. Delete the ImperiumAeterna folder in C:\Users\Your User Name\Documents\Endless Space\Disharmony\Modding
  2. Place the new ImperiumAeterna folder there instead

Save game compatibility between versions is not guaranteed. Generally speaking, each “full” number is not going to be fully save game compatible. E.g. 2.1.0 won’t be savegame compatible with 2.0.0, but 2.0.5 might be.


Uninstalling or Disabling

Disabling the mod is incredibly easy. None of the original game files are ever touched, so this is perfectly safe.

If you wish to play Vanilla:

  • In Game – Go to “Mods” and select “Endless Space”.

To play the mod again, simply switch back.

If you wish to Remove the mod permanently, add the following step:

  • Delete C:\Users\Your User Name\Documents\Endless Space\Disharmony\Modding\ImperiumAeterna



Release History

Missing versions have never been released and were development versions. We’ve tested many things which have been scrapped for various reasons.

v2.2.2 (Hotfix 2)

  • Fixed NullReferenceError when attempting inSystem colonization of Gaia planets.

v2.2.1 (Hotfix)

  • Fixed NullReferenceError with Colonized Aeterna.
  • Fixed Tolerant Trait Malus on Gaia Planets.
  • Fixed AI Parameters for New Technologies.


  • Added Gaia Planets and Gaia Terraformation.
  • Added Unique Planet “Aeterna”, with its own Wonder, Temple and Events.
  • Added 62 New Anomalies from Tiaximus’ fantastic Anomaly Overhaul.
  • New icons for Orbital Technologies and their improvements, created by bigbantha.
  • Orbital Trade Hub bonus “+1 Population” changed to “+1 Trade Route”.


  • Tweaked Diplomatic AI to lessen the Frenzied and Illogical Aggression in Disharmony.
  • Overhauled Diplomatic Relationship progression and added 2 more relationship statuses.
  • New icons for Planet Expansion Terraformations, created by bigbantha.
  • New icons for Planet Creation, created by Cosmocrat.
  • Added Planet Colours to Tier V Planets (Gas Giants and Asteroids) for consistency.
  • Added Planet Colours to Xenotourism Agencies Tooltip for consistency.
  • Added Planet Colours to Deep Space Facility Tooltip for consistency.
  • Added Planet Colours to Colonization and Terraformation Tooltips.


  • First Imperium Aeterna release compatible with Disharmony 1.1.58.
  • Combat Overhaul: Changed Long/Medium/Short Range Mechanics from Disharmony into Heavy/Normal/Light variants of each weapon.
  • Tooltip Bug Fixes, fixing bugs which Amplitude introduced in Vanilla patches.

Older Release Notes


  • Reworked the Ship Classes so there are now 5 distinct classes instead of minor variations.Imperium Aeterna Ship Classes


  • Made mod compatible with Endless Space v1.0.38.
  • Moved all language references to Localization file to create support for other languages.
  • Added Dyson Sphere by Tiaximus as 5th Orbital Improvement.
  • Included PlanetSize Terraforming by Tiaximus.


  • Added defense bonuses to Engine modules to make the higher ones more viable in Ship Design.


  • Custom Weapon Icons for the top tier weapons, following existing vanilla design.
  • Custom Icons for all new ‘Orbital’ System Improvements.


  • Rebalanced Weapon and Defense Modules in the biggest overhaul yet
  • Renamed almost all Weapons
  • Added MIRV (swarm) type Missile Weapon
    • Launches 5 warheads
    • Takes 2 rounds to reach target (medium speed, only 2 intercept chances)
    • Lower damage than other missile weapons
    • Designed to swarm and overwhelm defenses
  • Changed Missile type Missile Weapon
    • Launches 2 warheads
    • Takes 3 rounds to reach target (slow speed, 3 intercept chances)
    • Best crit chance of all missile types
    • Less predictable damage due to larger min/max damage range
  • Changed Torpedo type Missile Weapon
    • Launches 1 warhead
    • Takes 1 round to reach target (fast speed, only 1 intercept chance)
    • Predictable, flat damage output
  • Added several dual turret options among the beam weapons
    • These have reduced damage per shot to compensate and work great against smaller targets
  • Added new Beam Weapon ‘Deathray’
  • Added new Kinetic Weapon ‘Black Hole Generator’
  • New custom icons (which follow the existing design) have been created and included for both, and will be used in a new version as soon as the developers enable this functionality for custom ship modules.
  • Added secondary defense type to the Defense Module types
    • Flak deflects the occasional kinetic slug
    • Shields intercept/absorb low level missiles
    • Deflectors deflect/absorb some beam weapon damage
    • These effects are not present on the first 2 levels of each defense module type as they’re intended to provide benefit against a secondary weapon types several tech levels lower than itself.


  • Added the Planet Creation Technology.


  • AI will now Research the Technologies and build the Improvements.
  • Fixed the ‘Population Bug’ – The population capacity increase was never added to Planets.
  • Rebalanced the Construction Costs after a few Multiplayer Games.


  • Integrated Colored Anomalies.
  • Changed all Names & Descriptions of Orbital Entrenchment.
  • Drastic Re-balance of the Improvements.
  • Made the naming consistent with the rest of the game / tech trees: capitalisation, etc.
  • Fixed the system improvements and techs so they don’t have text ‘overflowing’ in odd ways in the game.
  • Changed the Improvement icons to ones I felt were more fitting, each has its own now. (Tried to keep them consistent with the improvements – unfortunately custom art work for System Improvements is not yet possible in mods.)
  • Created custom Tech Icons (yay pixel art!) for the 4 technologies.


(Click any of the links to go to the an appropriate page of either the mod or person in question)

Imperium Aeterna incorporates the following mods either partially or entirely:

Orbital Entrenchment Mod by Igncom1 – Provided the initial basis of the 4 ‘orbital’ technologies and their improvements. The version used in Imperium Aeterna has evolved a lot since then, undergoing re-balancing, bug fixing, custom tech icons and more.

Colored Anomalies by Luminality – Incorporated entirely. We’ve made extremely minimal modifications to this mod, mostly to make text easier to read.

PlanetSize Terraforming by Tiaximus – Incorporated with small modifications to costs for balance reasons.

Anomaly Overhaul by Tiaximus – Incorporated all new Anomalies.


Special Thanks to:

Tiaximus from the Endless Space Modding Community, for direct contributions to Imperium Aeterna.

ThorTillas from the Amplitude Studios Development Team, for helping track and resolve a bug with modding improvements.

Ail from the Endless Space Modding Community, for pointing us in the right direction with the same bug.

bigbantha, for his contributions of awesome custom created icons for Imperium Aeterna.

James Wells from Mana Pool, for endlessly playing and testing the mod for balance and bugs.

LFFPicard / Gary Thwaites from Mana Pool, for playing and testing the mod in his very first Endless Space games. Poor guy doesn’t even know what Vanilla looks like!

Medieval Gamer / Meghan Burton, another good friend of mine who also played and tested the mod in her first Endless Space games.

Lachrymosity, My dear wife who had the patience to let me spend countless hours on modding the game, talking her ears off about my ideas and also played and tested the mod.

Anyone else who indirectly contributed to this mod.

You, for reading this far!

Imperium Aeterna Downloads

Latest Version (Disharmony Version 1.1.58):
Download Imperium Aeterna v2.2.2

Older Versions (Disharmony Version 1.1.58):
Download Imperium Aeterna v2.1.0
Download Imperium Aeterna v2.0.0

Older Versions (Classic Version 1.0.38):
Download Imperium Aeterna v1.5.0 (Discontinued)

Please leave us some feedback, we love to hear from you! :-) If you like the Mod, please consider sharing it using one of the buttons below.

the author

Managing Editor of ManaPool, Peter lives in York, UK and is a great fan and master of turn-based strategy games. If he isn't playing one of those, you'll probably find him in a role-playing game instead. He's definitely not afraid to provide a straight up opinion on any game and has a strong like for indie developers. We all start small, after all.

  • Igncom1

    Best of luck!

    Just hope my initial coding for the orbital entrenchment was ok!

  • http://www.shadow1980.co.uk Evil Tactician

    It was more than ok Igncom1 :) When I ran into that, it inspired me to start looking at the modding side of things. I literally started the process by adjusting your mod and things continued from there.

    The idea is hopefully to assimilate more good ideas I run across from other modders, as well as add any modifications I come up with myself.

    We don’t want to dramatically change the game, but if that’s what it takes to make our gaming sessions more pleasant then that is exactly what we will do.

    We play the game extremely regularly in Multiplayer right now with the same group of people, so we’re getting a good idea of the aspects we feel could be improved. We’ve already felt some very positive effects from the changes!

  • http://www.shadow1980.co.uk Evil Tactician

    v1.4.0 released!

    Time to catch some sleep :-)

  • http://www.shadow1980.co.uk Evil Tactician

    v1.4.1 released :)

  • http://www.shadow1980.co.uk Evil Tactician

    v1.4.2 released.

  • http://www.shadow1980.co.uk Evil Tactician

    v1.4.8 released.

  • http://www.shadow1980.co.uk Evil Tactician

    v1.5.0 released.

  • DrDoodle

    Between the new ES patch and this mod I am looking forward to playing ES again, it beats CIV5 now. I like ALL the ideas you’ve incorporated and hope some of the ideas end up in the actual game(color coding being #1!) Thanks.

  • http://www.shadow1980.co.uk Evil Tactician

    Very glad you’re enjoying the game and the mod. A lot of the active modders are also part of the VIP team on the Endless Space forums, and help the developers with upcoming patches and add-ons (testing, feedback, etc.) – myself included.

    The developers are very responsive to ideas from the modding community and are certain to pick up elements that are extremely popular among the player base. If you are enjoying the game, it’s definitely worth voicing your opinion :)

  • Azhrey

    Thank you EvilTactician and everyone else who contributed to this mod. I hope to see it grow and get better, almost perfect…

    Thank you again.


  • Dan

    Thank you for this mod, really makes an enjoyable game even better :)

  • Saunen

    Is this mod compatible with 1.0.46? I ask cause planetsize terraforming doesn’t work it changes the size of the planets but not the population also a slightly more major thing the AI builds no combat fleets (only scouts and colonists) and they stockpile dust.

  • http://www.shadow1980.co.uk Evil Tactician

    The population capacity changes, not the population itself :)

    The fleets issue is a reported bug on the official ES forums – it’s something that puzzles both me as well as the devs, we haven’t found the root cause as of yet and aren’t even sure it comes from the mod :/

  • Saunen

    Loaded the save and tried the Terraforming again and it did not increase pop cap HOWEVER started a new game without crowded planet trait (+2 tiny/small +1 medium) and now it does work so either I’m missing something or the trait and Terraforming does not work together.

    Also tried some of the “fixes” from the forum thread no luck yet with AI fleets.

    I did notice something interesting though, the original ships the ones that one starts with as well as the original designs do not have your weapons/defense but rather vanilla modules not sure if that has anything to do with it…

    I will keep trying somehow i will find a way to play this mod I’m really looking forward too it :)

  • Mike

    Great mod! Brilliant! Its a must to have it! Unfortunatelly i had downgraded to version 1.4.9 due to no AI fleets problem.
    Anyway, speaking about new ideas, how about moon creation technology? Can you guys do something with heroes? Simply most of them are useless in vanilla version.
    Finally I wanna ask, does exist any community modding site for endless space, I mean something like Nexus modding comunnity site? I think it would be great idea to talk to them to start endless space modding site on Nexus. Somethink tells me they don’t mind…
    Thanks again!

  • udginvr

    Seems like there is a little problem with the Sowers. They have an unique technology “exotic thermodynamics” which lacks an ability to increase planet size from medium to large, preventing them from enlarging all the planets in the universe :)

    // Enlarge your tundra

  • udginvr

    Update to my previous comment (don’t think that this update needs to be approved and posted though).
    Indeed, there is missing block in “SimulationTechnologyExpansion.xml”. Comparing with original .xml there should be added something like this:




  • udginvr

    Damn… Styles won’t go through the posting form. Well, ok, just will post it here: http://udginvr.mass.hc.ru/tmp/TechnologyExpansion.xml

  • http://www.shadow1980.co.uk Evil Tactician

    You just needed your first post approving manually, that’s all :)

  • tirane

    What does the modification to power in some of the hulls do?

  • http://www.hotmail.com fred

    I’m getting an issue that when I start a new game an error message pops up and when I click to continue playing there is no universe, only the background.
    Pls help, thanks

  • Tar2010

    Thanks for a great mod :D

    I just wonder if this mod is updated to latest version of ES?

  • xaxa

    Well this mod doenst work on Disharmony expansion!

    everytime i get a nullpointer error and the game freezes.

  • Anthony Fenton

    I followed all the instructions, but every time I load the game, I do not see the mod at all, only the classic (version 1.1.17). Is there anything else I can do??

    • http://www.shadow1980.co.uk Evil Tactician

      The mod has not been updated for recent game versions, sorry.

  • Nitram99

    I see that this excellent mod is not updated to the new versions of ES such as Disharmony, but will it be or is this a dead project?

  • Zhan Ryushin

    Then update it.

    • http://www.manapool.co.uk/ Evil Tactician

      Whilst I can understand that an abandoned mod can be quite frustrating (I’m a gamer too in the end), please do bear in mind that no modder is ever obliged to update their mod or well, to do anything at all. Whilst I am currently updating it (finally, I know..) so far this has taken me over 20 hours and I expect to put another 20 in just to get the mod fully compatible in a way I’m happy with. It’s by no means a small task and it requires an amount of free time which I simply didn’t have in the last few years.

      Long story short, a small amount of appreciation is appreciated. I’m am however updating the mod as I had no idea it would become as popular as it did and I feel bad for it being in the state that it is. Bear with me.

  • Vanir

    Just started a game with this, event text seems to be missing from events now. Any way to fix that?

    • http://www.manapool.co.uk/ Evil Tactician

      I can’t really see why the mod should have caused that, but easiest way would be to wait for the new update, which is coming soon.

  • hunter

    how can i change the weapon tier every weapon is stuck to lvl 1 . is it a part of the game or a bug

    • http://www.manapool.co.uk/ Evil Tactician

      The mod is not compatible with the game version you are trying to run it with. I’m currently looking at resolving this.

  • http://www.manapool.co.uk/ Evil Tactician

    This is a rather late response, but I will look at resurrecting this, provided that is doable as a lot of things changes since I made this mod.

  • http://www.manapool.co.uk/ Evil Tactician

    Working on it!

  • http://www.manapool.co.uk/ Evil Tactician

    Great point and absolutely an oversight in 1.5, I will correct this for 2.0 – which is coming, I promise!

  • http://www.manapool.co.uk/ Evil Tactician

    A really late reply, but I wanted to address this nevertheless. I’m a fair bit more knowledgeable now and I think I know what happened in both instances.

    Terraforming: When increasing planet size, it essentially ceases to be a tiny or small planet – and thus will lose the associated bonuses from the trait. I may have to change the trait so you get a bonus on any planet, otherwise the trait will become pretty useless in this mod.

    E.g. Terraforming a Tiny Planet to a Small planet, gives you whatever the size increase is from that but DROPS one population from your trait, as the planet is now small (+1 bonus) instead of tiny (+2 bonus)
    Terraforming again to Medium, will make you lose the trait bonus altogether.

    This means the trait would only be useful in the early to mid game, after that it will lose all value as you can ‘simply’ increase the planet size. That’s a byproduct of the game mechanics I’m afraid.

    For the original ships, the weapon and defense modules in Imperium Aeterna 1.5 and earlier are ‘unique’ as far as the game code is concerned. The ‘old’ ones still existed too and I never updated the modules that the starter ships came with. It’s a really good spot!
    I’m rewriting most of the code when it comes to combat and modules in the next few releases, so these kind of issues should stay in the past.

  • http://www.manapool.co.uk/ Evil Tactician

    Version 2.0.0 has been released. This enables compatibility with Disharmony 1.1.58 (the latest version). Classic is NOT supported, by now everyone should have the DLC really and we don’t want to support two versions at the same time, given how fundamentally different the game is in Disharmony.

    We are also working on the next version of the mod. Expect more weapons, more defense modules, more balancing and quite possibly a few entirely new features.

  • http://www.manapool.co.uk/ Evil Tactician

    Version 2.1.0 has been released.

    => Tweaked Diplomatic AI to lessen the Frenzied and Illogical Aggression in Disharmony.
    => Overhauled Diplomatic Relationship progression and added 2 more relationship statuses.
    => New icons for Planet Expansion Terraformations, created by bigbantha.
    => New icons for Planet Creation, created by Cosmocrat.
    => Added Planet Colours to Tier V Planets (Gas Giants and Asteroids) for consistency.
    => Added Planet Colours to Xenotourism Agencies Tooltip for consistency.
    => Added Planet Colours to Deep Space Facility Tooltip for consistency.
    => Added Planet Colours to Colonization and Terraformation Tooltips.

  • http://www.manapool.co.uk/ Evil Tactician

    Version 2.2.0 has been released.

    => Added Gaia Planets and Gaia Terraformation.
    => Added Unique Planet “Aeterna”, with its own Wonder, Temple and Events.
    => Added 62 New Anomalies from Tiaximus’ fantastic Anomaly Overhaul.
    => New icons for Orbital Technologies and their improvements, created by bigbantha.
    => Orbital Trade Hub bonus “+1 Population” changed to “+1 Trade Route”.

  • invalidusername12

    How can I install this on a mac?

    • http://www.manapool.co.uk/ Evil Tactician

      Pretty much the same instructions, except you find the right folder here:

      Go to “User LibraryApplication SupportEndless SpaceDisharmony”

      All other steps should be pretty much identical, just the location of the modding folder is different :-)

  • SomeDude

    Hey, great mod so far, but is it normal that i have only one phase working in manual space battles, the 2 lasting rounds, both side don’t shoot anymore, is it part of the change in the combat ? Or is it just a “graphical” problem ?

    • http://www.manapool.co.uk/ Evil Tactician

      All phases should be working fine – if this isn’t the case, could you please visit our mod forum at http://www.imperium-aeterna.co.uk and report the bug. Please include a save game and a detailed description of the issue.

      It would be very helpful to know what weapons you and the opponents were using, as well as the battle cards played.

      I’ve heard of this issue before in another mod, but never in Imperium Aeterna. Are the ships still receiving damage? Perhaps it’s an issue with rendering the visual FX on your computer?

  • Eduardo Miguel Anastácio Marti

    Hi, this mod looks great, but every turn i am forced to assist a random battle that im not involved… only option is to go to desktop… this bug
    is irritating…

    • Eduardo Miguel Anastácio Marti

      the battle is between 2 Hunters and a scout! thats not mine…

  • Eric Liango

    Hello nice Mod! Small question did someone have translated the xml files in French ?

    • http://www.manapool.co.uk/ Evil Tactician

      Hi Eric,

      This is quite an old mod now, and I don’t believe it was ever translated to French. I was working on additional features and do have more assets, balancing, events, etc. in a development version but I got stuck on something and the developers (Amplitude) promised to provide some assistance/answer but then never did. As a result I had to abandon the work. It was quite disappointing, really..

      • Eric Liango

        Ok sad news anyway I don’t play anymore and believe all works now is on endless 2. This is some sort of big mod merging anyway

  • David Silva-Gonzalez

    Hi, I’m just wondering if there’s a place where you guys have posted, in detail, the exact things that the mod adds? I want to be able to know exactly how the AI diplomacy was changed, the exact anomalies and what they do that were added, etc etc. Thanks in advance!

  • Mr. Math

    Very late to the Endless Space party, but I made it. This game is so much fun I may buy Endless Space 2 as well. Thanks for the mod.

  • Liam Manuel

    Heya if any one is reading this i found a bug. The enemy cant use the tactical cards (eg weapon overlock or retreat) if theres any fix to it please reply

    • Peter Kersbergen

      Definitely not related to the mod.