Game Code
At the option menu, select cheat-password and type:
YAMOSHITO

Extra modes
After beating the East's section of the game go to the MAIN MENU and you will be able to see all the routes that you took. In your next game, you will also be able to play as the West. After you win the game with the west, you will unlock battle mode at the main menu. Battle mode allows you to play any battle you want with West or East.

Kessen (PS2) hints
# Play as the West

Successfully complete the game with the East.

# Battle mode option

Successfully complete the game with the East and the West to unlock a new option at the main menu that allows you to choose your battle mode. Any previous battle may be fought, with either the East or the West.