Rau Le Creuset is an officer in ZAFT serving as the commander of his own Le Creuset Team and the rival of Mu La Flaga. In truth he is actually a clone of Mu's father created by him who seeks to wipe out all of humanity, seeing them as not worth saving. He is the main antagonist of Mobile Suit Gundam SEED.
Rau was created by Al Da Flaga to serve as a worthy successor to him, seeing his own son Mu as inferior. He was produced alongside several other clones by Al Da Flaga and Professor Ulen Hibiki.
After killing Al Da Flaga by burning down his mansion, Rau left Earth to travel to PLANT and join ZAFT. He changed his name to "Rau Le Creuset" and donned a mask over his face to hide it, as it was the face of the man he hated most. Rau's piloting skills and charisma soon led to him rising through the ranks of ZAFT, eventually being given his own squadron in the Le Creuset Team. However, Rau held no real loyalty to the organization and was only with them to further his own ends. He also established ties with the radical anti-Coordinator organization Blue Cosmos and its leader Muruta Azrael, occasionally leaking information to them so he could play the two sides against each other.
Rau eventually enacts the final stages of his plan: cause the GENESIS to fire on Earth and wipe out all of humanity. Piloting his Gundam, the ZGMF-X13A Providence, Rau fought Kira in a fierce battle that ended with him being impaled. Dying, Rau smiled, believing that he had won. However, as this was going on, Athrun detonated Justice's reactor within GENESIS, destroying it and ensuring that Rau's plan did not succeed.