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Unity application that makes it easy to view assets from Uma Musume: Pretty Derby.

Version	Supported
JP (DMM)	✅
JP (Steam)	✅
KR	✅
Global	✅

⚠️ 🌍 EN/Global users ⚠️

In UmaViewer, set WorkMode to Default and Region to Global in the 'Other' Settings tab.

Currently only the default work mode is supported - you need to download assets using the Download All button in the game's settings for the viewer to work.

Requirements/Installation

Uma Musume: Pretty Derby with full data download is required to run the viewer.
Depending on your version and update status, the game stores its data in different locations

DMM/Steam Older installations : C:\Users\your_username\AppData\LocalLow\Cygames\umamusume(?)\
DMM/Steam Fresh installations : ...\Umamusume installation directory\Umamusume_Data\Persistent(?)\
In any case，confirm your file listing in target folder looks like this
- Target Folder\
  - meta
  - master\
    - master.mdb
  - dat\
    - 2A\...
    - 2B\...
    - ...\...

Download the most recent UmaViewer.zip file from Releases tab.
Extract the archive anywhere, can be extracted over previous version.
Run the UmaViewer.exe.
UmaViewer will try to automatically detect the game data folder.
- If it fails or shows an error, go to Settings → Other → Change DataPath and manually select target folder.

For Developers/Contributors

Unity Hub with Unity Engine Version 2022.3.62f1 is recommended. It should be possible to run it on newer 2022.3.X versions.
Clone or download and extract this repository.
Import and Open the project in Unity Hub, missing files should be automatically repaired.
Open the Assets/Scenes/Version2 scene.
- note: If there are errors in the console, JSON .NET For Unity may be required

PMX exporter maintainers should also read PMX Export Standard and Postmortem.

Live restoration maintainers should read 2026-10-01 improvement summary and publication boundaries. This source snapshot does not establish full visual parity and excludes local keys, extracted game assets, authorization audio payloads, and the native CySpring plugin. Current runtime prerequisites are listed below.

The current source includes runtime graphics settings and live-selection updates; it is not a claim of complete rendering parity. Running the viewer requires your own full game data and authorized keys. Supply DBBaseKeyText, DBKeyText, GlobalDBKeyText, ABKeyText, and AudioKeyText in the local Config.json next to the player, then restart. Key fields contain hexadecimal text without a 0x prefix; AudioKeyText is a nonzero key of at most 16 hex digits. Native physics requires your own authorized matching CySpringPlugin.dll (for Windows x64 players, in UmaViewer_Data/Plugins/x86_64); it is not distributed here. Excluded cri_auth and sound_proj.acf payloads are not required by the current source's audio decoder. No keys or local configuration are distributed. See current publication manifest for exact source hashes and exclusions.

Features


✓ - Working	/ - Incomplete	x - Unsupported


Viewing main character models/animations	✓
Swapping costumes/animations between characters	✓
Viewing chibi models/animations	✓
Viewing mob (NPC) models	✓
Playing facial animations, custom sliders	✓
Cloth/Hair physics	✓
Playing Live Audio with Lyrics	✓
Exporting animations to MMD	✓
Recording animations (.gif), screenshots	✓
Viewing Props, Scenery, Live scenes	/
Exporting models	/