Complete Chapter 17 "Rapids" to unlock this achievement.
This achievement is part of the storyline and CANNOT be missed.
At the main menu, hold LB + RB + LT + RT and press Down, Up, Y, X, Down(2), Y(2). Release LB + RB + LT + RT and a "Cheat" option will appear at the main menu. Select the "Cheat" option, then enter one of the following case-sensitive codes to activate the corresponding cheat function. Note: The codes have no effect when playing as King Kong.
Invincibility
Enter "8wonder" as a code. You will still take damage, but will not lose a life; however high falls and fire can still cause loss of life. Also, this code must be re-enabled with each new level.
One-hit kills
Enter "GrosBras" as a code.
Full ammunition
Enter "KK 999 mun" as a code.
Infinite spears
Enter "lance 1nf" as a code. Note: This code includes the number "1" in the second word. Press Reload to get the spears.
Get Revolver
Enter "KKtigun" as a code.
Get Shotgun
Enter "KKsh0tgun" as a code. Note: This code includes the number "0". Alternately, enter "KK BigBlast" as a code.
Get Machine Gun
Enter "KKcapone" as a code.
Get Sniper Rifle
Enter "KKsn1per" as a code. Note: This code includes the number "1"