Pause the game & enter Y, Y, Left Trigger, Up, X, Black, X, Y. You should hear a confrimation sound. If not, look above "resume" and it will say god mode on or god mode off.
Pause the game and press Y, Y, X, Down, Right Trigger, Left Trigger, Right Tigger, Up and you will have full ammo.
To get unlimited ammo in your current weapon, pause the game and enter: Y, Y, X,
Down, Right trigger, Left trigger, Right trigger, Up
One Hit Kill
At the pause menu enter:left trigger, right
trigger, y, x, b, white. You should hear a beeping
sound or it will say "one hit kill on" at the top.