Rayman Raving Rabbids’ tentative title during early development was Rayman 4.
The project began in 2005 as a planned 3D platform game, initially developed by Phoenix Interactive Entertainment. At that stage, Ubisoft treated it as the next main Rayman installment and referred to it as Rayman 4. Early concepts envisioned Rayman exploring familiar worlds, fighting enemies, riding creatures, and following a more conventional adventure story.
Development changed dramatically after Nintendo revealed the Wii. Ubisoft became concerned that the original project might not suit the new console’s audience and controls, so development was restarted at Ubisoft Montpellier. The revised concept emphasized Wii Remote-based minigames, humor, and the Rabbids, producing the 2006 party game Rayman Raving Rabbids.
This history causes a common mix-up: Rayman Raving Rabbids is often called Rayman 4 informally because it grew out of that sequel project, but Rayman 4 was the working identity of the earlier platformer concept, not the final retail title. The abandoned prototype and the released party game are related but substantially different.