Avoid unofficial "leaked" versions found on third-party sites, as these can contain malware or lead to permanent bans from the official community. Join the official Mario Multiverse Public Discord Server Head to the #demo-release (or similar) channel.
A legitimate concern: is the legal? The team has been transparent. They use no original Nintendo assets – every sprite, sound effect, and melody is original or licensed. They do not monetize the download nor accept donations. This falls under “fan art” and “parody” protections. However, Nintendo has historically issued takedowns for similar projects. The developers encourage downloading the demo now, as future availability is never guaranteed. mario multiverse public demo download high quality