The last M.U.G.E.N release, 1.1 beta 1, came out in August 2013 for Windows. On anything else you are left with Wine, Proton or an old DOS build. rugen is a new engine that reads the same files and runs natively on all three, so your collection comes with you.

Steam Deck

1. Switch to desktop mode and download the Linux tarball from the latest release.
2. Unpack it in your home folder, for example ~/Games/rugen.
3. In Steam, choose Games → Add a Non-Steam Game to My Library and pick the rugen binary.
4. Copy your characters into chars/ and stages into stages/ next to the binary. Desktop mode is the easiest way to move files.
5. Back in game mode, start rugen from your library.

rugen recognises the Deck by itself: the first launch goes fullscreen at 1280x800, every on-screen hint names the Deck’s buttons, the text is sized for the 7" screen, and the game pauses when you suspend. Nothing to configure. The full steps are in the install guide.

Linux

Pick the package for your distribution from the latest release:

• Fedora, RHEL, openSUSE: the .rpm.
• Debian, Ubuntu, Mint, Pop!_OS: the .deb.
• Anything else: the portable .tar.gz. It runs on any distribution with glibc 2.34 or newer, and updates itself from OPTIONS → UPDATE.

RAR archives need unrar, 7z or bsdtar on your system; zips and folders need nothing.

macOS

Download the macos-arm64 build for Apple Silicon (M1 and newer) or macos-x64 for Intel Macs, and unpack it. The builds are not signed yet, so the first time right-click rugen and choose Open, or run:

xattr -dr com.apple.quarantine ~/Applications/rugen

Your old MUGEN folder

Characters, stages and screenpacks load unchanged: .def, .cns, .cmd, .air, .sff, .snd. You do not need select.def; rugen builds the roster from the folder. If you also use Ikemen GO, the comparison page explains what carries over.

And online

Every build plays online with every other: a Deck against a Windows PC against a Mac, with rollback netcode. How to play MUGEN online walks through it.