Unlockables

The viblade is in the room with all the laser tripwires, on a stand in the centre
The M60 can be taken from a guard when you fail to get let in by the front gate guard
Oh, and sniper take up 3 inventory spaces, making them unwieldy, but the jackal and shockwave can be found in rooftops escape, and bridge assault respectively.
Unlockables
Falcon (Pistol 1) Nightclub Stakeout
Magnum (Pistol 1) Rooftops Escape
Magsec 4 (Pistol 1) Mansion Infiltration
Phychosis Gun (Pistol 1) Trinity Infiltration
M60 (Heavy 3) Mansion Infiltration
Plasma Rifle (Heavy 3) Temple Surveillance
Rocket Launcher (Heavy 3) Bridge Assault
DW-P5 (SMG 2) Nightclub Stakeout
UGL Liberator (SMG 2) Nightclub Stakeout
CMP-150 (SMG 2) Sewer Retrieval
RCP-90 (SMG 2) Jungle Storm
KSI-74 (Assault 2) Lab Rescue
FAC-16 (Assault 2) Trinity Escape (off dead ally)
SuperDragon (Assault 2) Outpost Rescue
Laptop (Assault 2) Trinity Infiltration
Viblade (Close Combat 1) Mansion Infiltration (red triplaser room)
DEF-12 Shotgun (Close Combat 2) Nightclub Stakeout
Combat Sheild (Sheild 1) Trinity Infiltraiton
Frag Grenade (Thrown 1*5) Nightclub Stakeout
Multi Mine (Thrown 1*5) Temple Surveillance
Hawk Boomerang (Thrown 1) Rooftops Escape
Achievements
You can get achievements for doing certain tasks in single play and multiplay modes. These achievements count to your gamerscore for your gamercard.
Also works with XBOX Live ☺
There are 50 in all and will give you 1000 gamerscore points in all.
Unlockable How to Unlock
10 Melee Kills Get 10 Melee kills in an Multiplayer mode
10 Kills in Team Killcount Get 10 kills in Team Killcount mode
Complete Single Agent Complete Single Player on Agent Difficulty
Complete Single Perfect Agent Complete Single Player on Perfect Agent Difficulty
Complete Single Secret Agent Complete Single Player on Secret Agent Difficulty
10 Kills in Killcount Get 10 kills in Killcount mode
10 Explosive Kills Get 10 kills using explosive in any Multiplayer modes
10 Sniper Kills Get 10 Sniper kills in any Multiplayer modes
100 Kills in Killcount Get 100 kills in Killcount mode
10 Headshot Kills Get 10 Headshots kills in any Multiplayer mode
100 Sniper Kills Get 100 Sniper kills in any Multiplayer modes
Played 10 Deathmatch games Play 10 Deathmatch games
100 Explosive Kills Get 100 kills using explosive in any Multiplayer modes
10 Territories Held Score 10 points in Territory Gain mode
100 Kills in Team Killcount Get 100 kills in Team Killcount mode
100 Melee Kills Get 100 Melee kills in an Multiplayer mode
100 Headshot Kills Get 100 Headshots kills in any Multiplayer mode
10 Minutes Survived Survive 10 minutes in Onlsaught mode
Complete Single Dark Agent Complete Single Player on Dark Agent Difficulty
Complete Co-Op Agent Complete Co-Op on Agent Difficulty
Complete Co-Op Secret Agent Complete Co-Op on Secret Agent Difficulty
1 Solo Mission On Dark Agent Complete 1 Solo misson on Dark Agent Difficulty
5 Co-op Missions On Dark Agent 5 Co-Op missons on Dark Agent Difficulty
1 Co-op Mission On Dark Agent Complete 1 Co-Op misson on Dark Agent Difficulty
1000 Explosive Kills Get 1000 Explosive kills in any Multiplayer Mode
1000 Melee Kills Get 1000 Melee kills in any Multiplayer Mode
1000 Headshot Kills Get 1000 Headshot kills in any Multiplayer Mode
1000 Sniper Kills Get 1000 Sniper kills in any Multiplayer Mode
Completed Co-Op Perfect Agent Complete Co-Op on Perfect Agent Difficulty
Completed Co-Op Dark Agent Complete Co-Op on Dark Agent Difficulty
Played 100 Deathmatch Games Play 100 Deathmatch games
Played 1000 Deathmatch Games Play 1000 Deathmatch games
Played 10 Dark-Ops Games Play 10 Dark-Ops games
Played 100 Dark-Ops Games Play 100 Dark-Ops games
Played 1000 Dark-Ops Games Play 1000 Dark-Ops games
1000 Kills in Team Killcount Get 1000 Kills in Team Killcount Mode
1000 Kills in Killcount Get 1000 Kills in Killcount Mode
10 Flags Captured Capture 10 Flags in Capture The Flag mode
100 Flags Captured Capture 100 Flags in Capture The Flag mode
10 Player Infected Infect 10 Players in Infection mode
100 Player Infected Infect 100 Players in Infection mode
1000 Player Infected Infect 1000 Players in Infection mode
100 Territories Held Score 100 Points in Territorial Gains mode
10 Rounds Survived Survive 10 Rounds of Eradication mode
100 Rounds Survived Survive 100 Rounds of Eradication mode
1000 Rounds Survived Survive 1000 Rounds of Eradication mode
10,000 CR Property Destroyed Destroy 10K CR of property in Sabotage
100,000 CR Property Destroyed Destroy 100K CR of property in Sabotage
100 Minutes Survived Survive for 100 minutes Onslaught.
5 Solo Mission On Dark Agent Complete 5 Solo missons on Dark Agent Difficulty
Kameo – Elements of Power
Acquiring Elemental Sprites
How to acquire various Elemental Sprites throughout the game.
Ash Rescue Halis.
Major Ruin Defeat the Shadow Troll in Lobster Hollow.
Rubble Defeat the Shadow Troll in the Forgotten Forest.
Pummel Weed Defeat the Shadow Troll in the Enchanted Kingdom.
Flex Defeat the shadow troll in Sulfer Cave.
Deep Blue Defeat the Shadow Troll in Water Cave.
40 Below Defeat the shadow troll in the ice cave.
Chilla Rescue Lenya.
Thermite Shadow Troll at Ogre Swamp
Snare Rescue Yeros
Thorn's Castle High Score Unlockables
For the unlockables below, you have to get the specified score or higher to get the unlockable.
Alternate Costume - Kameo 100,000
Making Backgrounds Video 500,000
Troll Song 1,000,000
Concept Video 1,500,000
Test Cutscene 2,000,000
Cheats Set #1 2,500,000
Water Temple High Score Unlockables
For the unlockables below, you have to get the specified score or higher to get the unlockable.
Alternate Costume - Major Ruin 2,000,000
Cutscene Videos 1,500,000
Alternate Costume - Ash 1,000,000
Alternate Costume - Kameo 500,000
Boss Fights 2,500,000
Cheat Set #3 3,000,000
Snow Temple High Score Unlockables
For the unlockables below, you have to get the specified score or higher to get the unlockable
Evolution of the Characters Video 500,000
Alternate Costume - Deep Blue 1,000,000
Music Player 1,500,000
Alternate Costume - Chilla 2,000,000
Character Model Video 2,500,000
Cheat Set #4 3,000,000
Thorn's Pass High Score Unlockables
For the unlockables below, you have to get the specified score or higher to get the unlockable. These high scores are for Thorn's Pass.
Alternate Costume - Kameo 2,500,000
Deleted Moves Movie 3,000,000
Evolution Videos 3,500,000
Alternate Costume - Flex 4,000,000
Animatic Videos 4,500,000
Cheat Set #5 5,000,000
Thorn's Airship High Score Unlockables
For the unlockables below, you have to get the specified score or higher to get the unlockable. These high scores are for Thorn's Airship.
Early Footage Video 500,000
Deleted Scenes Videos 1,000,000
Alternate Costume - 40 Below 1,500,000
Airship Concept Video 2,000,000
End Concept Video 2,500,000
Cheat Set #6 3,000,000
Total High Score Unlockables
For the unlockables below, you have to get the specified score or higher to get the unlockable. These high scores are for the total accumulated score.
Concept Art Set 1 9,000,000 Total
Concept Art Set 2 12,000,000 Total
Alternate Costume - Snare 15,000,000 Total
Animatic Videos 2 18,000,000 Total
Deleted Cutscenes Video 21,000,000 Total
Alternate Costume - Thermite 24,000,000 Total
Acquiring Crystal Eyes
Eye of Restoration - as Kameo, restores health
Under a shell in the enchanted Kingdom
Eye of Protection - Increases Kameo's Defense; Decreases Kameo's Attack
Near the top of the ancient tower.
Eye of Spirit (hidden in a hallway behind a sheet)
Past the portal to the mainland, there is a big door that needs lit dragon heads to open, flame them and go thru another door like it
Eye of Defense In the Hall of mirrors, use thermite's Mortar ability to blow up the statue in the middle.
Eye of Strength
Go to the chamber of Living Portraits in the centre of the Enchanted Kingdom's Palace. There you will see a statue of Thorn, who is holding an orb with a hole in the middle. Within that hole is the Eye of Strength. Morph into Thermite, and approach the statue. Aim a bomb shot so that a bomb will either hit the orb, or go into the hole where the Eye is. The statue will explode and the eye will drop to the floor, simply move to the pedestal to pick it up.