To change the game's difficulty, edit the defuser.ini file in the
game's folder using Notepad or a text editor. Look for the section that
begins with [HGame.Harry]. Look for the following lines:
fDamageMultiplier_Easy=1.2
fDamageMultiplier_Medium=2.0
fDamageMultiplier_Hard=3.0
Change the values to 0.1 to take less damage and make the game easier.
Save the file and start the game to take effect.