On December 24, 2022, an anonymous user on the Internet Archive uploaded the source code for Rayman 4, the original prototype for what would later become Rayman Raving Rabbids. The Rayman 4 prototype, which was known to be a 3D Platform game with beat'em up elements that involved the Rabbids as the game's antagonists, showcases several interesting features. Some of the content featured in the E3 2006 trailer can be found in the prototype such as rideable animal companions, interchangeable costumes, combat gameplay, and explorable settings such as a forest, cave, & gear temple.

Some newer never-before-seen content includes:
• Early unfinished cutscenes some featuring a witch doctor from Rayman 3: Hoodlum Havoc.
• Explorable Rabbid bases/lairs with programmed Rabbid enemies.
• Rayman utilizing several projectile weapons.
• Other explorable worlds such as a village setting and a sphincter-inspired level.
• Rayman controlling Rabbid vehicles such as a hovercraft and large robots.
• When receiving damage, Rayman loses his clothing except for a leaf covering. This costume was repurposed as the Rayomz skin in Rayman Legends seven years later.

The console versions contain several unused animations for Rayman.

The Xbox 360 version of the game has three achievements that are impossible to unlock: "Greatest Rayman Ever", "Rayman Loves Drawing" and "Rayman Loves Challenge". They all involve beating every challenge in Score Mode. To unlock these, the player must accumulate 174,000 points to unlock the final challenge, but the accumulated perfect score of every other challenge only goes up to 173,000.