Right-click the ZIP and select "Extract to MarioMultiverse_CLB". Running the .exe directly from the compressed folder will cause assets (specifically the music tracks) to fail loading.
If you cannot find a working today, do not despair. The game is unstable, the co-op barely functions, and your anti-virus will scream at you. But for hardcore platformer fans who are tired of sterile, polished releases, this chaotic, multiverse-shattering fangame is the most innovative Mario has felt in a decade. mario multiverse closed beta download
Because the game uses memory injection for its "Glitch" power-up, many antivirus programs flag it as a false positive. Create a folder called C:\ParadoxGames and add it to your antivirus exclusions before extracting. the co-op barely functions