Cheats
On the main menu hold L + R and input DOWN, BLUE, UP, YELLOW, DOWN, DOWN, UP, UP. When the triggers are released, an extra cheat menu will appear. While playing, input the following codes via the cheat menu for the following effects:

8wonder ... Invulnerability (damage visual still present).
GrosBras ... One-hit deaths on.
KK 999 mun ... Space between each word. Adds 999 rounds to current weapon magazine.
lance 1nf ... 1 is numeric one, space between words. Press reload to summon lance.
KKcapone ... Current weapon becomes submachinegun.
KKtigun ... Current weapon becomes handgun.
KKsn1per ... 1 is numeric one. Current weapon becomes bolt action rifle.

Input the following codes on the main menu for higher game functions:

KKst0ry ... Unlock all chapters.
KKmuseum ... Unlocks all extras.