Hidden in the files for Star Fox 64 are what seem to be remnants of an unused first-person turret mode. Several files reference a stage with the initials "SB", with its header file, fox_sb_poly.h, being titled "スター ブレード 擬き" (Sutā burēdo ki). This translates to "Star Blade Imitation", named after the 1991 on-rails space shooter by Namco, where the ship's guns can only be used in first-person. Dylan Cuthbert and other developers of the original Star Fox admitted to being heavily inspired by Star Blade, claiming that one of their main goals was to recreate the experience of the game.

The file, fox_play.h, defines 3 scroll types of levels: corridor, all-range mode, and "JYUZA", or "銃座モード" (Jūza mōdo), which translates to "Gun turret mode". This file also defines five player modes: ARWING, TANK, SUB, HUMAN, and P_JYUZA, While the SB stage is listed with the other corridor stages, it still specifies that it's in the "JYUZA" category. The SB stage itself appears to be a shortened copy of the Area 6 stage devoid of any content except for one Moras enemy, suggesting that it and other stages were meant to be played in the turret mode during development.

In the game's source code, stages such as "SB", "CL" or "Colony", and Area 6 are subtitled "Great Fox", suggesting that the Great Fox mothership was also intended to use the turret mode. It would likely have been about firing lasers and guns from the ship while trying not to take damage, as there is a string for the ship's health bar named gfox_life. The game's levels, such as the Landmaster stages, are organized into overlay groups to save on memory; Area 6 strangely isn't grouped within the turret mode stages, but Sector Y is.

This unused game mode was restored via a fanmade patch on October 30, 2024, taking a few liberties to make up for the missing code and assets.