Zero Requiem

Zero Requiem is a plan created by Lelouch and carried out with the assistance of Suzaku and possibly C.C. to end all war and to usher an age of peace. The plan involved focusing all of the world's hatred on himself, then have Suzaku disguised as Zero and kill him, dissipating the hatred and allowing the world to focus on more important matters than fighting, such as reconstuction, thus facilitating peace. Lelouch arranges the public execution of the Black Knight leaders and the U.F.N. representatives. When Suzaku, disguised as Zero, interrupts and kills Lelouch, the culmination of the Zero Requiem as they had planned. By directing all the hatred of the world onto him, Lelouch's death will serve to facilitate peace. He dies smiling, saying he is the one who both destroys worlds and creates them. Suzaku is left to play the role of Zero. Nunnally can only watch in shock. When Lelouch falls near her, she takes his hand and realizes that he has sacrificed himself on purpose to bring world peace

Aside from Lelouch, Suzaku and C.C., several other key characters knew about Zero Requiem, including Jeremiah Gottwald, Lloyd Asplund, Cécile Croomy, Sayoko Shinozaki and Nina Einstein, while others such as Nunnally, Kallen, the core Black Knights members and Cornelia only realized it during and after his execution.