Mods — Getting Started — Rebellion

Last updated: 2026-10-10A Rebellion mod is a folder of SYNX files and images. How it is laid out, how it lies over the game, how to install and test it and play it in a squad. A ready example — the Karambit mod.

Mods — Getting Started

A Rebellion mod is a folder of SYNX text files and images. No programming is needed: a mod changes the game's numbers and adds its own — weapons, items, armour, smithing recipes, drops, images, model textures and texts.

Download the example — the Karambit mod 1.1.0 (zip, 6 KB)

Exploders drop a bent blade, and the smith forges a knife and the blade into a new weapon. Every file of the mod is commented in detail: unzip it, open the files and change the numbers — the easiest way to start.

PageWhat it covers
New WeaponsYour own weapon on a game weapon's body, left- and right-click attacks, the smith's recipe
Items, Armour & DropsItems, armour, key-activated items, who drops what, recipes
Abilities, Shaman & MobsNumbers of abilities and shaman nodes, health and damage of mobs
Images, Textures & TextIcons, model textures, glow maps, names and descriptions
Field ReferenceEvery field of weapons, items and mobs and what it does

1. The mod folder

karambit/
  pack.synx                 manifest — the only required file
  balance/
    items.synx              new items and drops
    weapons.synx            new weapons
    loadout.synx            which items are weapons
  assets/
    items/
      karambit.png          weapon icon
      bent_blade.png        item icon
  locale/
    en.synx                 names and descriptions in English
    ru.synx                 the same in Russian

2. The manifest, pack.synx

The manifest uses SYNX active mode: the !active line turns on the :i18n marker, so the name and description are written in every language at once. The game takes the player's language, or English if it is missing.

synx
!active

id karambit
kind mod
version 1.1.0
author Your name
apeiron rebellion_mod_karambit

name:i18n
  en Karambit
  ru Керамбит

description:i18n
  en Exploders drop a bent blade; the smith forges a knife and the blade into a karambit.
  ru С взрывников падает гнутое лезвие; кузнец скуёт из ножа и лезвия керамбит.
FieldWhat it is
idThe mod's unique name: lowercase Latin letters, digits and _. The game skips a mod with any other id and writes why in the log
kindmod. The value dlc is reserved for official add-ons
versionRaise it on every change: a squad plays together only when everyone has the same versions of mods
authorShown in the settings
apeironThe mod's id in Apeiron: a guest without the mod is offered to download it from there. Not needed for a private mod
name, descriptionName and description in Settings → Mods & DLC

3. How a mod lies over the game

Next to Rebellion.exe there is a balance folder — the game's open balance files. It is your reference: every entry and every number is there. A mod's balance/<name>.synx is merged into the game's file of the same name:

  • a new key is added — this is how new weapons and items appear;
  • a matching key is merged deeper — name only the fields you change;
  • a number or list is replaced whole — if you change a list, repeat what the game had in it;
  • the value null removes the key.

A mod that doubles the knife's damage is one file, balance/weapons.synx:

synx
weapons
  knife
    damage 24

Field names are strict. A typo is a load error: the run will not start, and the reason is in the log. Every name is in the reference.

4. Install and test

  1. Put the mod folder in %LOCALAPPDATA%\APERTURESyndicate\Rebellion Saves\mods\ — your own mods folder, which Apeiron does not touch.
  2. Start the game: Settings → Mods & DLC — the mod is listed and switched on. You can switch it off there too.
  3. Images and text apply after restarting the game, balance from the next run.
  4. Something is wrong — open logs\rebellion.log in the data folder and look for packs: lines: they show which mod was read, which was not, and why.

5. Mods, statistics and achievements

A run with a mod that changes balance (has files in balance/) does not count towards lifetime statistics, achievements or the leaderboard: a mod can give you a weapon with any damage, and records would stop meaning anything. At the start of such a run the game shows a "Modded run" notice. Mods with only images and text do not affect statistics.

6. Mods in a squad

Everyone in a squad must have the same mods enabled, in the same versions. A guest without the host's mod is not let in: the game shows which mods are missing and opens them in Apeiron if they are published there.

7. What a mod cannot do

The game's code is closed, so a mod changes only data — numbers, lists, images and strings:

  • no new models, animations or sounds — a new weapon borrows a game weapon's body; models can be recoloured with your texture;
  • no new mechanics — new weapons and items are built from what the game can already do;
  • no new mobs, bosses or abilities — you can change the numbers of existing ones.

8. Publishing in Apeiron

Players install published mods in Apeiron, on the Rebellion page, in the Mods tab. For now we publish mods ourselves: send the mod folder to [email protected], we will review it and publish it under your name.

What a mod may contain and the licence you give us to publish it are in the End User Licence Agreement, Sections 4 and 7. We will not publish a mod that breaks the game, saves or online play, contains someone else's work without rights, or breaks the Terms of Service or the Online Play & Squad Rules.

Mods — Getting Started — Rebellion | AS Docs