This is a small guide for extracting and modifying assets or code from games made with the Unity engine. Feel free to contribute.
Unity game folder structure
│ *.exe
└───*_Data
│ globalgamemanagers
│ globalgamemanagers.assets
│ level0
│ level0.resS
...
| levelN
| levelN.resS
│ sharedassets0.assets
│ sharedassets0.assets.resS
...
| sharedassetsN.assets
| sharedassetsN.assets.resS
| resources.assets
├───Managed
│ Assembly-CSharp.dll
│ Assembly-UnityScript.dll
│ Mono.Security.dll
│ mscorlib.dll
│ System.Core.dll
│ System.dll
│ UnityEngine.dll
│ UnityEngine.dll.mdb
│ UnityEngine.Networking.dll
│ UnityEngine.UI.dll
├───Mono
│ │ mono.dll
│ └───etc
│ └───mono
│ │ browscap.ini
│ │ config
│ ├───1.0
│ │ DefaultWsdlHelpGenerator.aspx
│ │ machine.config
│ ├───2.0
│ │ │ DefaultWsdlHelpGenerator.aspx
│ │ │ machine.config
│ │ │ settings.map
│ │ │ web.config
│ │ └───Browsers
│ │ Compat.browser
│ └───mconfig
│ config.xml
└───Resources
unity default resources
unity_builtin_extra
* : Name chosen during building
| File/Directory | Description |
|---|---|
| *.exe | Executable file of the game |
| *_Data | Data folder containing the game resources |
| level0-levelN | Files containing game scenes data, each scene has its own file |
| sharedassets0-sharedassetsN | Game assets are split into sharedassets and .resS files (sharedassets.assets.split0 - ..splitN on platforms like Android/iOS) |
| resources.assets | Raw Assets found in the project resources folders and their dependencies are stored in this file (as well as raw audio files, even if outside of Resources folder in Unity, AudioClips with references to .resource and info such as audio size/offset still stored inside .assets) |
| Managed | Folder containing unity DLLs |
| Assembly-CSharp.dll | DLL file containing compiled C# files |
| Assembly-UnityScript.dll | DLL file containing compiled UnityScript files |
Extracting and editing code
C# and UnityScript files are compiled into the Assembly-CSharp.dll and Assembly-UnityScript.dll DLLs respectively, which can be found inside the Managed folder.
DLLs can be decompiled using ILSpy or dnSpy which allow modifying and recompiling assembly files.
If DLLs are missing from the managed directory, try dumping them using this tool MegaDumper
Extracting assets
Assets are stored in the .assets and .resS files. Content of these files can be unpacked with one of these tools :
| Tool | Description |
|---|---|
| UtinyRipper | uTinyRipper is a tool for extracting assets from serialized files (CAB-*, *.assets, .sharedAssets, etc.) and assets bundles (.unity3d, *.assetbundle, etc.) and conveting them into native Engine format. |
| Unity Studio | A tool for exploring, extracting and exporting assets from Unity games and apps. |
| Unity Assets Bundle Extractor | UABE is a tool that allow modification of assets file and extraction of assets in usable formats (png/tga for textures, obj for meshes). |
| Unity Assets Explorer | Can extract textures to .DDS format, meshes to .43 format. |
| QuickBMS with this script or this one for webplayer | |
| DevXUnityUnpacker | A (paid) tool with a friendly GUI meant for restoring unity projects by inputting the built game/app including a previewer for individual files as image, hex, text etc. |
| UnityEX | Tool for extracting/converting files from .assets bundles and replacing files (Mostly used for replacing textures). |
DDS files :
The DDS files can be opened/converted/edited with this gimp plugin or this photoshop plugin.
Another way of extracting meshes and textures :
Use 3D Ripper DX (doesn't support 64 bits binaries) or Ninja Ripper.
Alternatives:
| Tool | Tutorial |
|---|---|
| RenderDoc | Tutorial on how to use RenderDoc. |
| Intel® Graphics Performance Analyzers | Tutorial on how to use the Intel Graphics Analyzers to extract graphics. |
Hacking memory
Cheat engine have a feature called Dissect mono that can help hacking game's memory. This video series about using cheat engine is really useful.