Code Geass: Hangyaku no Lelouch

Code Geass: Hangyaku no Lelouch (コードギアス 反逆のルルーシュ) is the first video game based on the anime and manga series of the same name. It was released on October 25, 2007 for the Nintendo DS and published by Namco Bandai Games. The story is loosely based on the story of the anime/manga series, but with many decisions left in the player's hands along with alternate stories which can be accessed through New Game+. The player, as in Lost Colors, acts as a new member of the Black Knights, Lelouch Lamperouge's rebel faction.

Unlike the other games in the series, Hangyaku no Lelouch plays as a traditional RPG. The player must choose from options like attack, skill, and item to defeat their enemy. The battles in the game are always fought with Knightmares, with different frames representing different characters, though the enemies usually vary (an assault copter is fought in the first battle). Additionally, different characters can be called by using the microphone feature.

Castor rui Britannia and twin brother Pollux rui Britannia are introduced as Britannian princes in one unlocked game scenario. They serve as the antagonists of the alternate storyline, allowing Britannians and Britannian knights such as Cornelia, Euphemia, and Jeremiah to be recruited.