--- title: Casualties Unknown Mods: How to Install Them with BepInEx description: Step-by-step BepInEx setup for Windows, Linux and Steam Deck, and why a mod might not load. url: https://casualtieswiki.wiki/mods/how-to-install-mods/ --- Mods # How to install Casualties Unknown mods Where a mod ends up - 1 **Casualties Unknown game folder**Holds the game's .exe; open it with Manage > Browse local files - 2 **BepInEx/**Created when you unzip the loader here - 3 **BepInEx/plugins/**Appears after the first launch - 4 **YourMod.dll**Plus any dependencies the mod page lists _Folder layout from the community Steam guide on modding, dated 9 October 2026._ **Short answer:** to install Casualties Unknown mods, unzip **BepInEx 5 x64** into the game folder, run the game once, then put each mod’s .dll into `BepInEx/plugins`. There is no Steam Workshop support, so this is done by hand. confirmed Almost every mod for the game loads through BepInEx, a plugin loader for Unity games. Once it works, adding more mods takes seconds. ## How do you install BepInEx for Casualties Unknown? The steps below come from the [Steam community modding guide](https://steamcommunity.com/sharedfiles/filedetails/?id=3816289819). confirmed ### Windows - Download BepInEx 5 for Windows x64. The guide links version 5.4.23.4, and the popular co-op mod links 5.4.23.5. Use whichever your mod asks for. - In Steam, right-click the game, then **Manage > Browse local files**. The default path is under `steamapps\common\`. - Extract the zip straight into that folder. Accept “Replace all files” if asked. - Run the game once so it generates its folders, then close it. - If a `BepInEx/plugins` folder now exists, it worked. ### Linux and Steam Deck Use the **Windows x64** zip of BepInEx here too, because the game runs through Proton. confirmed - Extract it into the game folder. - In Steam, open the game’s **Properties**, and under **General > Launch Options** paste `WINEDLLOVERRIDES="winhttp=n,b" %command%`. - Run the game once, then close it. If `plugins` did not appear, create it inside `BepInEx`. On a Steam Deck, do all of this in Desktop Mode. Players on the forum say it works the same way as any other Linux install, and that no mod manager supported the game on Linux at that time. reported ### macOS The guide’s author only got this working through CrossOver, by opening the whole folder in it, installing Arial fonts through CrossOver’s store if needed, and adding `winhttp.dll` as a DLL override in the Wine configuration. unverified Steam lists Windows 10 as the only supported system, so expect rough edges. ## Where do Casualties Unknown mods go? Most mods are a single .dll or a zip containing one. Extract it and place the files here: confirmed `/BepInEx/plugins/` Some mods differ, and the mod’s own page always wins. The [co-op mod](https://casualtieswiki.wiki/mods/multiplayer/) copies into the game root, and skin mods add a `CustomSprites` folder. Check the mod page for required libraries too. CUCoreLib, for example, is a dependency of many mods and has 36,038 downloads for that reason. confirmed ## Why is my mod not working? The community guide lists four checks, in this order. confirmed | Check | What to look for | | --- | --- | | BepInEx location | Beside the game’s .exe, not inside a nested folder like `BepInEx_win_x64_5.4/` | | Mod location | The .dll is in `BepInEx/plugins` | | Dependencies and version | The mod page’s requirements match your game build | | The mod’s own steps | Some mods need extra files or config | Two more causes are worth checking on your own: - **Wrong game build.** Mods were written for the demo, and the full game launched on 9 November 2026 with a large set of changes. The developer also said the demo would not receive those changes, so a mod for one may not load on the other. - **Two mods doing the same job.** Installing two skin changers or two libraries of the same kind is a common source of conflicts. Remove half your mods, test, and narrow it down. Mods are code that runs on your PC. Download from a mod’s Nexus page or its author’s own GitHub, and avoid re-uploads. ## Do you need a mod manager? Not for a handful of mods. A manager helps when you want to switch sets of mods on and off without moving files. confirmed | Manager | What it adds | Downloads on 9 Nov | | --- | --- | --- | | [Alexx_’s Mod Manager](https://www.nexusmods.com/scavprototype/mods/31) | A Mods tab in the settings menu that toggles BepInEx plugins | 7,477 | | [Mod Manager by Foxiecub](https://www.nexusmods.com/scavprototype/mods/495) | Toggles by renaming files to `.dll.disabled`, with presets | 2,021 | Both are in-game toggles, so they still need BepInEx installed first. ## Is there Steam Workshop support for Casualties Unknown? No. Steam lists no Workshop for the game, and players on the forum have asked for it. reported Mods are distributed through Nexus Mods, GitHub and the modding Discord. Nexus had 544 mods listed for the game on 9 November 2026. confirmed Once your loader works, the [best mods list](https://casualtieswiki.wiki/mods/best-mods/) is the next stop, and [console commands](https://casualtieswiki.wiki/mods/console-commands/) work without any mod at all. ## How do you remove mods? Delete the mod’s .dll from `BepInEx/plugins`. To remove modding entirely, delete the `BepInEx` folder and the `winhttp.dll` and `doorstop_config.ini` files that came with it, or use Steam’s **Verify integrity of game files**, which restores anything the mods changed. Back up your saves first if you want to keep a modded run. ## Sources Last checked 9 November 2026. Marks: confirmed = official notes, in-game text or a recording of the game; reported = two or more players; unverified = one source. - [Modding Casualties: Unknown, Steam community guide](https://steamcommunity.com/sharedfiles/filedetails/?id=3816289819) · BepInEx steps per platform - [Steam forum: steam deck modding](https://steamcommunity.com/app/4576490/discussions/0/563667940587687380/) · player reports - [Steam forum: workshop support](https://steamcommunity.com/app/4576490/discussions/0/564797531878420154/) - [Alexx_'s Mod Manager on Nexus Mods](https://www.nexusmods.com/scavprototype/mods/31) - [Mod Manager by Foxiecub on Nexus Mods](https://www.nexusmods.com/scavprototype/mods/495) ## More in Mods - [Best mods The most downloaded mods, what each one changes and how to combine them.](https://casualtieswiki.wiki/mods/best-mods/) - [Multiplayer How to install the Casualties Together co-op mod, what it changes and why friends cannot join.](https://casualtieswiki.wiki/mods/multiplayer/) - [Skins Which skin mod to use, how to install skins and how they sync in multiplayer.](https://casualtieswiki.wiki/mods/skins/) - [Console commands How to open the console, which commands are confirmed, and menu mods that replace typing.](https://casualtieswiki.wiki/mods/console-commands/)