Star Fox 2

Star Fox 2 was the 1995 unreleased Super NES sequel to the original Star Fox.

Well, not officially released. It was leaked online, then Fan Translated into English. The game was actually fairly complete, lacking only some polishing touches for release, but was otherwise quite playable -- a small Game Mod fixed even this up, and the ROM is fully playable in emulators.

But the unreleased game did not go to complete commercial waste -- two-thirds of its code was recycled for Star Fox 64, and many of 2's gameplay mechanics were reused for Star Fox Command. But whereas reaction to Command was very mixed, the leaked Star Fox 2 ROM was well-received by gamers.

Storywise, 2 continues the 1993 game's Canon, but was the last officially-developed work to do so. In 1997, Star Fox 64 rebooted the game's universe from scratch.
 * Cool Shades: General Pepper again, naturally.
 * Fan Translation: The only way this game saw a version with English text.
 * There existed indeed, at one point, an official english version of this game, as evidenced by Nintendo Power screenshots.
 * The Power of Rock: Macbeth's music.
 * The Sixth Ranger: Miyu and Fay. Fara (or "Lady") was planned to be in this game and appeared in some earlier alpha versions, but was dropped from the final release.
 * Transforming Mecha: Your ship can rotate it's wings down and use them as legs when you're on the ground. In Star Fox 64, the transformation aspect was removed, and the walking mech became a separate tank-like vehicle, the land-master.
 * The Psycho Rangers: The Star-Wolf Team. This would have been the first appearance of them.