Banjo-Kazoomie

Banjo-Kazoomie  was a racing game that was to be released on the original Xbox. The game would have players construct their own cars and race them. It is speculated that the game was an early prototype of the infamous Banjo-Kazooie: Nuts & Bolts.

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Quote from a developer of Banjo Kazoomie, Brendan Gunn: "I’ve always wanted to do a racing game. I got to spend two weeks working on a prototype racing game for the Xbox. It was codenamed ‘Banjo-Kazoomie’, and it was a kind of kart racer, but you constructed the karts out of different parts, so I guess it was kind of a precursor to ‘Nuts & Bolts’. But for those two weeks I was doing the driving mechanics for it"