Casualties Unknown Mods and Compatibility
Mods are the main reason players keep searching after their first runs. The failure mode is almost always the same: a loader version mismatch or two mods fighting over the same behaviour.
Quick answer
- Install the loader first, launch the unmodded game once, then add one mod at a time.
- Match the mod to the game build it was published for; a version mismatch is the most common failure.
- Keep a clean copy of the game files so you can roll back without reinstalling.
- Multiplayer mods must match on every player and every machine.
How mods work here
Most Casualties Unknown mods are loaded by a mod loader rather than by dropping files into the game folder. The loader reads the mod assemblies and plugins at startup, which is why the loader version and the mod version have to agree.
The practical consequence: a mod is not "installed" just because the file exists. It is installed when the loader logs that it loaded, and the game still launches normally.
Mod categories and what to expect
| Category | What it changes | Risk |
|---|---|---|
| Multiplayer | Adds co-op sessions or syncs players | High: every player must match versions |
| Quality of life | UI, inventory, keybinds, readability | Medium: usually safe, occasionally conflicts |
| Visual and cosmetic | Skins, lighting, comfort filters | Low to medium: watch performance |
| Accessibility | Larger text, color cues, reduced motion | Low |
| Utility | Debug tools, save inspection, logging | Medium: can change save behaviour |
Start with one category. A quality-of-life mod list is easier to debug than a mixed list of five categories added on the same evening.
The install order that avoids most breakage
- Update the game and launch it unmodded. Confirm the baseline works.
- Install the loader. Launch once and confirm the loader log exists.
- Add one mod. Launch again. If it fails, you know exactly what caused it.
- Add the next mod. Repeat until the list is complete.
- Write down the exact versions. A working list without version numbers is not reproducible.
This takes longer than copying a folder. It also means every failure has one obvious suspect, which is the whole point.
Version matching is the real compatibility rule
A mod that worked last month can fail after a game update, even if nothing about the mod changed. The loader, the game build and the mod were compiled against specific interfaces; when one moves, the others may not.
Before installing, check three version strings:
- The game build the mod page lists as supported.
- The loader version the mod expects.
- The mod's own release version.
If you cannot find all three, treat the mod as experimental and test it on a separate save.
A safe way to test a new mod list
Use a throwaway save, a short run and a fixed checklist:
- Does the game reach the main menu?
- Does a new run start?
- Does the mod's main feature appear once?
- Does the game survive one combat encounter and one inventory change?
- Does it exit cleanly?
If any answer is no, remove the last mod you added. Do not start changing five things at once; that turns debugging into guessing.
Multiplayer mods need identical lists
Co-op is the highest-risk category because every player has to run the same compatible set. A host with an extra quality-of-life mod can desync or refuse a join from a player who does not have it.
Agree on a list, record the versions, and have every player install from that list before the session. If someone joins late, they install first and join second. The multiplayer guide covers the session checklist in more detail.
Run this checklist
0 / 6 doneFrequently asked questions
Do I need BepInEx for Casualties Unknown mods?
Most plugin-style mods use BepInEx. Check each mod page: if it ships a DLL plugin, it needs a loader. The setup guide walks through the install order.
Why did my mods stop working after an update?
The game build changed and the mod was compiled against an older interface. Check the mod page for a build that matches the current version.
Can I use mods in multiplayer?
Only when every player runs the same compatible set. Treat the mod list as part of the session setup, not an afterthought.
Are mods safe to install?
A mod is executable code. Download only from the mod author's published page, keep a clean game copy and avoid bundles from unknown mirrors.
How do I remove a broken mod?
Remove the mod folder, restore the loader to its previous state if needed, and launch unmodded to confirm the baseline still works.
Set up the loader correctly once
The BepInEx guide is the checklist that stops most mod failures before they start.