Body Surf Ability
Select extras from the main menu, then select cheats and enter the following.
Code: Right, Right, Left, Down, Up, Up, Up, Down
Complete story mode on normal difficulty to unlock Hard Mode.
Reveal Karen Parker's location
Finish all Scientist Consume events to reveal Karen Parker's location
Earn a Gold in every event to unlock the more-difficult Platinum Events
When you are playing the game you will want to build up your skills in how to play and maneuver properly. There are are about 5 bosses you're going to have to fight and the end boss is called Mother. She has 14 symptoms of the virus in the game and she is the biggest infected that you have to defeat. She's about 50 feet tall and can destroy...
Keep Your Upgrades
When you finish the game you can start a new game and keep all of your upgrades from the previous game.
Upgrade Movements First
If you upgrade the movements first you will be faster and you will evade the police quite easily.
More Visible Collectibles
Use Infected Vision (or Thermal Vision) to find hard-to-see Landmark and Hint Collectibles
Use Helicopter for EXP exploit
Mission 22/31 will require you to steal a Black Ops helicopter to destroy a Hive. There is no time limit and the alert meter will not increase until the Hive is destroyed. Use this time to gain as much EXP as possible without penalty.