You probably thought that Sega's official abandonment of the Dreamcast back in 2001 meant we wouldn't see any new, Sega-produced Ecco the Dolphin games for that system. If so, you thought wrong. That's because a newly unearthed prototype of the Dreamcast's cancelled Ecco II: Sentinels of the Universe has hit the Internet, more than 15 years after it was made.

The prototype build, uploaded by the game preservationists at Hidden Palace, is dated February 19, 2001, less than a month after Sega announced it would stop supporting the Dreamcast and step away from the hardware business for good. It comes to the Internet via a large lot of Ecco Dreamcast assets acquired by Hidden Palace, and the site promises "more exciting (and long overdue) [Ecco] stuff in the weeks to follow."

In addition to the ripped GD-ROM version, which is fully playable on PC Dreamcast emulators, Hidden Palace also released a self-boot CDI image that can be burned to disc and played on actual Dreamcast hardware (and hopefully on a real CRT television, for that authentic 2001 console gaming experience). We can thank the Dreamcast's extremely broken copy protection technology for that little wrinkle and for the widespread piracy that helped doom and/or popularize the system back in its day.

The prototype's early 2001 build date likely makes this one of the final development versions of the game and probably one of the last Sega-produced Dreamcast discs ever made. Before this playable prototype was dumped, the only concrete details we had of the game came from a 2007 video of a very similar prototype being played on a Dreamcast Katana development kit.

Unlike other canceled Dreamcast projects, (like Toejam and Earl 3), Sega didn't transition Sentinels of the Universe development to living consoles like the PS2 and Xbox. That means this prototype is our only hint of how the series would have developed after 2000's Ecco: Defender of the Future, which still remains the last Ecco title ever released (note to Sega: it's past time for a reboot for this franchise; also: Space Channel 5 and Chu Chu Rocket).

While the Sentinels of the Universe prototype is fully playable and handles very similarly to its predecessor, it's lacking basic features like sound effects, music, or much in the way of story and explicit goals (save a few above-water hoops to jump through and NPC dolphin placeholders to talk to). You'll run into a lot of glitches and unpolished art, too, which isn't too surprising, since Hidden Palace says that "development on the game had only just begun before it was canceled." The prototype is also stuck in debug mode, which clutters the screen with messages regarding things like frame rate and runtime errors.

Despite all those issues, it's still pretty exciting to swim around new, "official" undersea worlds in a franchise (and on hardware) we thought was abandoned long ago. Now if someone can dig up a playable version of the Dreamcast demo for Streets of Rage 4, our Sega nostalgia zone will be well and truly sated.