Kung Fu Panda Cheats

Invincibility: Story Mode Cheat
On the Main menu, go to extras, and then cheats. Once there, enter the following code to make Po invincible during the story mode gameplay. (Whether this can help you with the "Invincible" achievement or not is unknown) NOTE: This cheat does not stop you from earning achievements.

Down, Down, Right, Up, Left: Invincibility

Unlock all multiplayer characters
On the main menu, go to extras and click on the "cheats" button:

Left, Down, Left, Right, Down: Unlocks all multiplayer characters

4x Damage Multiplyer
On the main menu, go to extras and click on the "cheats" button:

Up, Down, Up, Right, Left: 4x Damage Multiplyer

Big Head Mode
On the main menu, go to extras and click on the "cheats" button:

Down, Up, Left, Right, Right: Big Head Mode

Infinite Chi
On the main menu, go to extras and click on the "cheats" button:

Down, Right, Left, Up, Down: Infinite Chi

Unlock Dragon Warrior Outfit (Multiplayer)
On the main menu, go to extras and click on the "cheats" button:

Left, Down, Right, Left, Up: Unlock Dragon Warrior Outfit (Multiplayer)