Begin a new game and press [Esc] to display the options menu.
Select the "Enter Cheat" option, and type DV (case-sensitive).
Press [Enter] to display the cheat options.
Tip1: Each character is designed for a particular type of combat;
learn the strength of each character and emphasize that skill in
Tip2: Take a moment when entering a room to make sure it's new and
not one you've visited before. It's very easy to get disoriented
Tip3: In multiplayer games, practice banking weapon shots off walls
in order to nail opponents around corners and behind obstructions.