Killzone: Liberation Codes -

Bonuses:
Complete the indicated campaign in single player mode under the listed difficulty setting to unlock the corresponding bonus.
Concept art pack #1: Campaign 3-4 under the normal difficulty setting. 
In-depth character profiles #1: Campaign 1-1 under the easy difficulty setting. 
In-depth character profiles #4: Campaign 4-4 under the easy difficulty setting. 
Jukebox: Campaign 2-4 under the normal difficulty setting. 
Multi-player Character Cobar: Campaign 4-4 under the hard difficulty setting. 
Multi-player Character Evelyn: Campaign 4-4 under the normal difficulty setting. 
Wallpaper pack #1: Campaign 1-4 under the easy difficulty setting. 

Bonus characters:
Complete the indicated task to unlock the corresponding character.
Cobar: Complete the game under the hard difficulty setting. 
Commando: Complete two player co-op mode. 
Metrac: Complete the game under the easy, normal, and hard difficulty settings. 
Specialist: Win 10 games in Ad-Hoc or Infrastructure Multi-player mode. 
Stratson: Win 100 games in Ad-Hoc or Infrastructure Multi-player mode. 

Abilities:
Get the indicated number of points by completing challenges to unlock the corresponding ability. To choose an ability, press Square at the weapon selection screen
50% more health: 300 points 
Placement C4 twice as fast: 100 points 
Carry three grenades: 20 points 
Carry three smoke grenades: 140 points 
Carry three syringes: 60 points 
Carry four pressure mines: 220 points 
Unlimited ammunition: 480 points 
Close combat damage doubled: 260 points 
Trip mines disarmed twice as fast: 180 points 
Your partner has 50% more health: 340 points