Back when Double Helix Games was still working on Killer Instinct for Xbox One, they provided a behind-the-scenes look at development by way of Gametrailers.

While an incredibly interesting look at the origins of the sequel in its own right, the short documentary also included a brief peek at the prototype Double Helix put together to show Microsoft as their bid for the job. Complete with blank models and Street Fighter IV’s training mode, the early build wasn’t much to speak of, but it did include glimpses of the game that would go on to be Killer Instinct.

However, it looks as if there might have been one more step between that rough proof-of-concept and the final Xbox One title.

Andrew Borman of Past to Present Online recently got his hands on another Killer Instinct prototype that looks much closer to the game we know today but also happens to be running on a different system: Xbox 360.

Yep, you read that right. According to Borman, the footage he was given demonstrates another early build that was made specifically for the Xbox One’s older sibling, though for what purpose remains unknown. It’s possible this prototype served as another stepping stone for Double Helix on their road to snagging the Killer Instinct license, or even that the game was originally planned for Xbox 360 before being shifted to the then next-generation console.

(Editor’s note: Borman noted in a follow-up email that the build is way too far along to be part of the pitch Double Helix put together for Microsoft.)

You’ll no doubt notice that the game is incomplete. Tons of assets appear to be missing, such as textures and stages, and Thunder even retains the mannequin-esque placeholders used in the earlier build.

In any case, this is just another interesting footnote on Killer Instinct’s road back to the fighting game community, so be sure to check it out and let us know what you think.

Source: Past to Present Online