To unlock the following characters, go to the Custom Character screen, press triangle and enter the corresponding passwords:
CHARACTER - PASSWORD
Alanna (Necris) - phayder
Ariel (Iron Clad) - jihan
Easy Damage Amplification:
While playing "Heatray" in multi-player Deathmatch mode, get a Damage Amplification by destroying the Dark Walker after it drops.
Berserk room on "Biohazard":
On Biohazard, there is a Berserk power-up just past a Bio Rifle and some stairs, along with a green button just before the stairs. Shoot the green button and it will turn red. Anyone inside the Berserk room will be locked inside, and there will be green toxic waste that can kill you.
Walls on "Deimos":
On the Deimos map, there are orange and green appearing walls. You can walk and shoot through them. At the top of the map are two of these orange walls that are circular in shape, which allow you to reach a sniper rifle.
When using the hoverboard, hold down the Right Analog-stick and press the Left Analog-stick Left or Right to spin in that direction.
Unlock the following characters by performing the corresponding tasks:
CHARACTER - HOW TO UNLOCK
Akasha - Unlocked after final mission.
Damian - Unlocked after early mission in chapter 4.
Kragoth - Unlocked after early mission in chapter 4.
Lauren - Defeat in deathmatch sidemission in chapter 2.
Loque - Unlocked after CTF in chapter 5.
Malakai - Unlocked after early mission in chapter 4.
Matrix - Defeat in deathmatch sidemission in chapter 3.
Scythe - Defeat in deathmatch sidemission in chapter 4.
30 Minutes or Less - Complete 100 VCTF matches played to at least 3 captures.
Ace - Get the "top gun" award in 20 matches.
Armadillo - Get the "roadkill" award in 10 matches.
Beeing a Hero - Return 100 orbs in warfare matches.
Big Game Hunter - Get the "big game hunter" award in 10 matches.
Brain Surgeon - Get the "head hunter" award in 10 matches.
Connect the Dots - Complete 100 warfare matches played to at least 3 points.
Deathwish - Get the "bullseye" (self-destruct to destroy an enemy) award in 20 matches.
Delivering the Hurt - Have over 20 minutes of "udamage time".
Does Not Compute - Complete chapter 3.
Dont Taze Me Bro! - Get the "combo king" award in 10 matches.
Flag Waver - Complete 100 CTF matches played to at least 3 captures.
Goo God - Get the "biohazard" award in 10 matches.
Got Your Back - Complete 10 mission in co-op.
Hammerhead - Get the "jackHammer" award in 10 matches.
Hat Trick - Achieve a hat trick in 10 CTF or VCTF matches.
Have a Nice Day - Get the "rocket scientist" award in 10 matches and "flak master" award in 10 matches.
I Need Some Backup - Complete 1 mission in co-op.
I See How It Is - Complete an instant action match in every game mode.
Jack of All Trades - Kill an enemy with every vehicle (except hoverboard).
Killjoy - End Sprees in 20 matches.
Let's Get It On - Complete a multiplayer match in every game type.
Lock and Load - Complete chapter 1.
Never Saw It Coming - Have over 20 minutes of "invisibility time".
Not in Kansas Anymore - Complete chapter 4.
Off to a Good Start - Get the "first blood" award in 40 matches.
Paint the Town Red - Complete 100 deathmatch or duel matches played to at least 20 kills..
Pistolero - Get the "gun slinger" award in 10 matches.
Seeing Red - Have over 20 minutes of "berserk time".
Serial Killer - Get the "killing spree" award in 20 matches.
Shard-O-Matic - Get the "blue streak" award in 10 matches.
Sir Slays-a-Lot - Get the "monster kill" award in 20 matches.
Soldier's Blood - Complete chapter 2.
Spice of Life - Play a match with every mutator, using only 1 per match.
Strongest Link - Get the "shaft master" award in 10 matches.
Survival of the Fittest - Have over 10 minutes of "invulnerable time".
Around the World - Win a multiplayer match on every map.
Bag of Bolts - Complete chapter 3 in insane.
Get a Life - Get 200 kills in multiplayer on 50 different days.
Just Business - Complete chapter 2 in insane.
Like the Back of My Hand - Collect every power up on every map.
Thanks to All the Little People - Complete a campaign in co-op.
Open War - Complete chapter 4 in insane.
Fear the Reaper - Defeat akasha and complete the campaign in insane.
Online Champion - Win 500 online matches.
Untouchable - Reach 20 kills against a god-like bot in instant action without dying.
Unreal! - Earn all Bronze, Silver, and Gold trophies.