Never-before-seen footage from a Legend of Zelda: Ocarina of Time prototype featuring magical portals has been revealed for the first time. The Legend of Zelda: Ocarina of Time underwent a number of changes during development, as Nintendo was using it and Super Mario 64 as testing grounds for the Nintendo 64's 3D hardware.

Loads of unused data from The Legend of Zelda: Ocarina of Time was discovered in the 2020 Nintendo "gigaleak," including scenes shown in early tech demos and screenshots sent to '90s gaming magazines. It's clear Nintendo was still experimenting with Nintendo 64 hardware when developing Ocarina of Time, especially when a second collection of prototype data was discovered on an F-Zero X cartridge. Areas in the 3D Zelda game were once planned to be much larger and pack in more NPC character models. These ambitions were presumably too much for the N64 to handle, causing levels to be scaled back into the more familiar forms players can explore in the Nintendo Switch Online + Expansion Pack and other versions of Zelda: Ocarina of Time today.

Related: Zelda: Why Ocarina of Time's Water Looks Worse on Switch

It was revealed earlier in 2021 that there was once a Zelda: Ocarina of Time tech demo with portals by Giles Goddard, who worked at Argonaut Games and helped develop several Nintendo games. Goddard revealed on the MinnMax show his creation a proof-of-concept demo for Ocarina of Time, which featured magical portals in Hyrule Castle. He said the portals were attached to movable crystals, and the player could even see what was on the other side of the portals in reflections on the crystals' surfaces. Goddard was again asked about the tech demo on Twitter recently, and he revealed footage of the portals within Hyrule Castle for the first time.

Goddard explained the Zelda: Ocarina of Time demo was made in either 1996 or '97, and he had asked one of the artists on the game for the visual assets needed to make the demo. He also divulged the fact that he probably shouldn't have any backups of the demo in his possession. It's unclear whether these prototype Ocarina of Time backups will be preserved online or if they will remain in Goddard's (or Nintendo's) possession.

It's always fascinating to view these early versions of classic games and wonder what might have been. The Nintendo gigaleak was were filled with information about the various iterations of The Legend of Zelda: Ocarina of Time and how Nintendo chose to present the game to audiences during its development. This all-new footage from the portal demo offers a look at a version of Ocarina of Time that could have stolen Portal's thunder by nearly a decade.

Next: Zelda: Ocarina of Time Switch vs. N64 Video Shows What's Missing

Source: Giles Goddard/Twitter