Banjo X was a remake of Banjo-Kazooie that Rareware were developing for the Xbox in 2005, which was eventually cancelled and redeveloped into Banjo-Kazooie: Nuts & Bolts. In an effort to surprise players who're familiar with Banjo-Kazooie, the game would have been advertised as a straightforward remake with very few changes, but in reality it would diverge wildly from the original as it progressed. Characters would develop a sense of self-awareness about having to relive the scenarios featured in Banjo-Kazooie, and they'd change their behaviour accordingly. The levels and gameplay setpieces would differ too: for example a giant termite queen would burst out of Ticker's Tower in Mumbo's Mountain, and Conga would use his oranges to defeat her. Humba Wumba and other characters from Banjo-Tooie would also appear, possibly along with some of its locations.The art style for Banjo X strongly resembled that used for Nuts & Bolts, although early assets for the game (such as a redesigned Mumbo Jumbo model that was used for testing character lipsync animation) featured rounder silhouettes compared to the appealing constrasting blocky/curved contours used in the final art style. In a behind-the-scenes featurette created for Rare Replay, artist Ed Bryan explained that they tried out this smoother high-poly approach at first, but felt it lacked the charm the characters had in the original games - this led him to push his designs in the more stylised direction seen in later assets and in the final Banjo-Kazooie: Nuts & Bolts.
Veteran Rareware devs Steve Mayles and Ed Bryan have kindly shared a number of the game's unused assets and animations over social media in recent years, as well as insights into the team's vision for the game.
- It's known that Humba, Mumbo, Tiptup, a Jinjo, and a "Bully" had all been modelled (and in the case of Mumbo and Humba, animated) by Ed Bryan prior to the game's cancellation. These designs would have differed from the ones that were eventually created for Nuts & Bolts, and likely had the rounder art style seen in Mumbo's lipsync test animation. Conga and the Ticker Queen had also been modelled and animated by Steve Mayles before production ceased.
- Grant Kirkhope composed a reorchestrated version of the theme for Mumbo's Mountain before development was cancelled. Some of this music was reused for Banjo-Kazooie: Nuts & Bolts's teaser trailer.