1,012 ratings
Rim-Effect: Core
Mod, 1.2, 1.3
File Size
23.712 MB
May 7 @ 2:44am
Nov 10 @ 12:02pm
10 Change Notes ( view )

Subscribe to download
Rim-Effect: Core



See change notes for any future updates.

05/07/2021: Release

Rim Effect is a large overhaul mod series, adding the story, races, objects, and conflicts of Mass Effect universe into RimWorld. The Mass Effect elements are not meant to stand out, and as such are blended into the RimWorld style by utilising the same naming conventions and writing styles.

Much like Vanilla Factions Expanded, the Rim Effect mod series comes divided into sub-modules, firstly to allow the players to pick exactly what elements they want in their games, secondly to ease the production and design process.

Rim Effect Core is the primary module for this mod series, upon which all other sub-modules will depend. Core module introduces a brand new ultratech faction - Systems Alliance, with their own planet-side bases, apparel, weapons, backstories and structures. It’s certainly the biggest mod ever made by us, and potentially the biggest mod on the workshop right now, featuring dozens of new structures, multiple new power sources, an in-depth ability system with tech and biotic powers, lots of new weapons, apparel, animals and other unique mechanics.

Two new storytellers are also present in the game: John Paragon and Jane Renegade. Using the storyteller is NOT a requirement to play this mod, but those storytellers offer interesting new approaches to the game itself.

These mods will utilise Vanilla Expanded Framework and all the code within it, as well as Humanoid Alien Races framework, kindly provided by Erdelf. As such, both our Framework and Humanoid Alien Races are required to play with this mod.


We are currently not aware of any issues. If you believe you encountered a bug, please submit a hugslib log alongside an explanation of how the bug occurred. If you don’t do that, I promise you I won’t get back to you. We need the logs to troubleshoot. We don’t need screenshots or your mod lists, or names of your pawns. We need logs.

To get hugslib logs, make sure you have a Hugslib mod running, then go to the dev console and press the green 'Share logs' button. Post the link in the comments.

You might also need to download a Hugslib Token Fix mod if you encounter issues with log uploading.

If you have feedback in regards to a specific mechanic, feel free to leave a comment in the comment section below!


Oskar Potocki, Project Lead and Design Lead;
Oracle of Thessia, Secondary Project Lead;
erdelf, Programmer;
Taranchuk, Programmer;
xrushha, Programmer;
Alastair, Artist;
Erin, Artist;
Kriptobaam, Artist;
Neronix, Programmer and Artist;
Helixien, Artist;
Shakesthespeare, Artist;
Sarg Bjornson, Programmer;
Kikohi, Programmer;
Luizi, Artist;
Sparky, Artist;

Sounds sourced from original games. Property of Bioware.

(CC BY-NC-ND 4.0)[creativecommons.org]

Q: Video shows vehicles. I built them and they are just props! why?
A: We are still waiting for the Vehicle framework to incorporate those as actual vehicles!

Q: CE Compatible?
A: Yes.

Q: There is already a Rim-Effect: Asari of the Rim mod. Why release this?
A: Helixien, author of the original Rim-Effect mod is part of this team. We decided that RimWorld modding community deserves a new, big, expansion-size Mass Effect mod and we should leave the old Asari of the Rim mod behind. The future is now, old man.

Q: I dislike X mechanic, can I disable it?
A: No, the entirety of the mod comes as one package, with every mechanic tied to other mechanics. If you dislike something, simply don’t use it in game - there is plenty of elements in this mod. Avoid the ones you dislike.

Q: Do I need Vanilla Expanded framework for this to work?
A: Yes. It’s a framework with vast amounts of interesting, important code.

Q: Do I need Humanoid Alien Races framework for this to work?
A: Yes. Whilst this mod itself doesn’t add any alien races, funnily enough the Humanoid Alien Races framework includes other bits of code we found useful.

Q: Where are other Mass Effect races?
A: They will come in future modules. This module is only focused on building the foundations of the series by adding an Alliance faction, lots of new spacer furniture, abilities etc.

Q: Can I add it to an ongoing save? Can I remove it?
A: Yes, you can add it whenever you like. You cannot however remove it, so make sure to backup your save!

Q: Does this mod remove anything from vanilla game?
A: No. Whilst we brand it as overhaul, what we mean by that is that it’s massive, and it’s bound to change the way you play late game, however not one element of the vanilla game is changed, removed or otherwise altered.

Check out our collection at:

Popular Discussions View All (8)
Nov 15 @ 7:20am
Tending problems?
Big Island Pineapple
Sep 1 @ 4:57am
Armor issue
May 22 @ 12:57pm
< >
Oskar Potocki  [author] Nov 26 @ 10:20am 
At some point they won't be props :)
Zurg The Otter Nov 26 @ 9:57am 
So just a thought. Am currently doing a Rimeffect playthru. And I noticed that the mako tank and alliance shuttle props (not the srts shuttles) cost an awful alot of plasteel considering that they don't actually do anything. Like I said, just a thought.
Darkveld Nov 25 @ 7:21pm 
Is there a way to get more than the 4 abilities from maxing out the omni tool or biotic amp?
Oskar Potocki  [author] Nov 25 @ 5:33am 
No, a shield like that is a special ability for armors like the N7 Destroyer armor in the N7 pack, and Spectre armor in this pack. It won't be applied to ALL armors.
Thanks for the answer. Is that a feature planned for later? I think there's a shield belt in one of your other mods that does something similar but it feels kind of unfair since raiders wont use them often.
Oskar Potocki  [author] Nov 25 @ 2:51am 
Just a flavor text.
Looking through the descriptions of armour items they reference kinetic barriers but I can't see any actual stats on those and they don't seem to have any effect. Am I missing something? I thought they'd be like vanilla shields except they'd be able to shoot but I can't see any shield effect.
Tomadeira Nov 23 @ 1:32pm 
Is there a way to mute Ymir mechs? Just ten of them enough to spam their sound constantly. Changing volume range to 5 in sounddefs xml didn't seem to help. I don't mind the sound in battle etc it's only bothering me when they're idling on charging stations
Minotaur Nov 20 @ 8:23pm 
Absolutely fantastic mod, as always!

However I do have one question: I'm currently working on the Colony Growth quest and I can't seem to be able to create a kitchen that the quest will accept. So far I've created five other rooms (bedroom, lab x2, rec room, dining room) from scratch to the necessary size requirements and the quest lists them as complete. However I've built the last room with every type of stove and butcher table available, lit, heated, and floored the room, yet the quest still lists it as incomplete. I've even had my pawns start cooking meals in the new room. Is there something I'm missing in order for it to see the room as a "kitchen"?
Oskar Potocki  [author] Nov 20 @ 1:41pm 
Right clicking an ability makes it auto cast.