Update [Tue 11th Apr, 2023 00:05 BST]:
Tim Stamper has now posted a follow-up tweet featuring video footage of Dream 64. In it, he notes how it was "probably" shown at Japan's Nintendo Shoshinkai show (Space World) in 1996. In the video, there's a pirate mentioning how "the Nintendo 64 treasure does exist after all". See it in motion below:
Original article [Sun 9th Apr, 2023 08:15 BST]:
Rare had a successful run during its time with Nintendo but not every project necessarily saw the light of day. One of these games was a role-playing title codenamed Project Dream. It started out on the Super Nintendo and was eventually scaled back during the Nintendo 64 era before parts of it morphed into other projects.
While a Super Nintendo version is believed to have existed, it seems now we've got actual photo evidence of Dream 64, after the Rare co-founder Tim Stamper randomly uploaded a single photo on social media, with the following text attached: "Arr....! So it's true... Dream 64 does exist after all...!".
In the picture, you can see a Nintendo 64 development cartridge running on an N64. Next to it is an NTSC Super Nintendo version of the Dream Project. The N64 cart is labelled the "latest version of Dream 64" and dated 21st November 1996.
Famous Rareware composer Grant Kirkhope responded to a message about Stamper's tweet suggesting it had the intro on it as well as "some" gameplay. While it's unclear just how far development got, as already noted, it eventually turned into other projects like Banjo-Kazooie.
In recent years, this isn't the only unreleased Rare project to resurface online. The Nintendo 64 game Dinosaur Planet (which went on to become Star Fox Adventures on the GameCube) was leaked online, and the unreleased version of GoldenEye 007 XBLA for Xbox 360 also got an unofficial release.