Unlockable List
Enter the following during gameplay:
Code - Effect
Up, Left, Down, Left, Down, Up, Up, Left - Big heads
L1, Left, L1, Left, R1, Right, R1, Right - Disco Mode
Up, Up, Up, Up, Up, Up, Down, Right, Up - Low Gravity
All team members must beat an episode with 100%: Defeat Leader In Single Player Mode upgrade a weapon with a character and do not miss during the level: Humans and Creatures.
The Boat level
When you have to get the boat downstream, kill off the two Sintrek, the Grenadak, and the other monster. Do not worry if one of your characters dies; just take out the monsters. When this is done, destroy the two stones in the river, then the bridge (completely obliterate it), then do the same for the water mill. Then, destroy the dock. Do not be in the boat when you do this. After the dock is destroyed, jump into the boat, release the controller, and an intermission sequence will start.
The Stranger level
Do not worry if one of your characters dies; they will come back to life after you finish the episode. However, to make sure you have a nearly 100% chance of winning, get on top of the roofs when no monster is there. Once this is done, you can snipe away at your enemies. After you shoot, go all the way back to the mountain that touches the roof, but do not go down. Shield, because the monsters will shoot your building. If you are all the way back, you will not get hurt. Do not worry, the building cannot crash and you will be fine doing this.
Custom
Get two 100% head shot statuses in a row.
Defeat Leader
Have all team members beat an episode with 100%.
Humans and Creatures
In Single Player Mode, have a character upgrade a weapon. Also, do not have any character miss during the level.
Level Select
Beat the game twice.
Team Power
Get two head shots in a row.
Level Skip
At the Story Mode game select screen press L1, Square, R1, R1, R2, Square, L1, R1, R2.