Banjo-Kazooie: Stop ‘N’ Swop and the Secret That Never Came

Banjo-Kazooie contains six Ice Keys and Eggs hidden in levels that have no in-game method of collection — they exist in the data, they render correctly, but every door and pad that would give access to them is locked in ways the game provides no tool to unlock. This was Stop ‘N’ Swop: a feature that required you to physically swap cartridges mid-game to transfer data.

The feature relied on the N64’s RAM retaining data for a few seconds after cartridge removal — long enough to boot a second game and read the transferred values. Nintendo discovered this trick and quietly patched it in later hardware revisions, making the feature unworkable on most systems. Rare had to abandon it.

Banjo-Tooie, the 2000 sequel, contains placeholder rewards for the Stop ‘N’ Swop items — including a secret level called Hailfire Peaks that references the Ice Key specifically. These rewards were eventually implemented in the Xbox Live Arcade re-releases in 2008, a decade after the original plan.

The six eggs were colour-coded: pink, blue, cyan, red, yellow, green. Each one was visible in a specific level behind a locked door. For years, players extracted them via GameShark and found they were complete functional items — not placeholder data. Rare built the entire feature, shipped it, and then could not use it. The game still contains everything they made.