List of Donkey Kong Land III pre-release and unused content
From the Super Mario Wiki
This is a list of pre-release and unused content for the game Donkey Kong Land III.
Donkey Kong Land III was going to have the sub-title "The Race Against Time;" it was later removed, presumably due to the fact that the other two installments in the Donkey Kong Land series did not possess sub-titles, so it would seem slightly pointless to give Donkey Kong Land III one.
Donkey Kong Land III has an unused track in the game. It is an 8-bit version of Rocket Run, the music played in Rocket Rush in the SNES version of Donkey Kong Country 3: Dixie Kong's Double Trouble! It is unknown whether a Rocket Rush-style level was intended to be implemented in the game, or whether this was a test track.
Rattly the Rattlesnake
A glitched version of Rattly the Rattlesnake is available by hacking (specifically, by using the GameShark code 010600DF). He has some properties left over from Donkey Kong Country 2: Diddy's Kong Quest and Donkey Kong Land 2, including jumping high, and being able to jump on any enemy, including enemies that the Kongs cannot jump on (such as Buzz and Bristles). A Rattly icon can also be seen on the bottom of the screen as well, which is taken from Donkey Kong Land 2. However, upon entering or exiting a bonus level, Rattly will become glitchy, turning into an immobile smoke ball, which is the same sprite used when switching Kongs. It is likely that Rattly is simply leftover code from Donkey Kong Land 2, since Donkey Kong Land III's game engine is essentially a modified Donkey Kong Land 2 game engine.