300: March To Glory cheats and cheat codes for Sony PSP

25,000 Kleos:
While playing, pause the game play, then push Down, Left, Down, Left, Up, Left. 
Note: You can enable this code only once.

Beat Giant Immortals:
First try to break their armor by using a spear, after attack them with 
any weapons. There is a gray bar on the screen, which indicate the Giant 
Immortals armor amount. When fighting against the 2nd Giant Immortal, 
he will run away. He will start to restore health. Go to the statue he 
is beside, then push it on top of him.