Cemu

Cemu emulates the Wii U and now runs very well, even on modest hardware. All the difficulty lies in the format of your games.

1. Choose the right format — it changes everything

• WUA — the preferred choice. This is the format recommended by Cemu itself: compressed, it bundles the game, its updates, and its DLC into a single file, and requires no keys at all.
• WUX and WUD — older encrypted formats. These require a keys.txt file.

If you're starting from scratch, convert straight to WUA: you'll skip the whole keys business.

2. If you need to use keys.txt

1. Create a text file named exactly keys.txt, in the same folder as Cemu's executable.
2. One key per line, each linked to a title ID — extracted from your own console.
3. Cemu reads them on startup and decrypts on the fly.

Cemu's documentation is clear on this point: these keys must be extracted from your own console. Homebrew tools run on your Wii U retrieve your common key and your games, which you then transfer via USB or your local network.

3. Recommended settings

• Graphics API: Vulkan, with shader cache enabled.
• Let Cemu compile its shaders on first launch: the initial stutter goes away afterward.
• Community graphics packs fix the framerate and resolution of many games.

4. Not working?

• "Unable to launch game" on a WUX → missing or wrong key in keys.txt.
• Persistent stuttering → check that the shader cache is properly enabled and kept between sessions.