Aliens: Colonial Marines (Xbox 360...

Complete the following achievements to unlock Xbox Live Gamerscore points.

Achievement	How to unlock
... But No Cigar (20 points)	Rescue a teammate from a Close Encounter.
Adaptive Morphology (30 points)	Upgrade every Appearance slot once for a Xenomorph class.
Adios, Muchachos (20 points)	Gib two enemies at once.
Another Bug Hunt (5 points)	Complete a Challenge.
Another Day in the Corps! (20 points)	Complete Distress.
Anytime, Anywhere (20 points)	Kill a Crusher without it damaging you.
Arbitrarily Exterminated (30 points)	Kill 2179 Xenomorphs.
Bad Feeling About This Drop (20 points)	Complete Sulaco Falls.
Coming Outta the Walls! (10 points)	Kill a Xenomorph climbing on the walls or ceiling.
Distinguished Service Medal (30 points)	Complete all Challenges.
Don't Count Me Out (5 points)	Revive a teammate.
Dragged Queen (20 points)	Complete Home.
Eat This! (10 points)	Kill a Xenomorph with a shotgun at very close range.
Entry Prohibited (20 points)	Kill 10 Xenomorphs that are using vents.
Field Modified, Kill Certified (20 points)	Upgrade every slot for a weapon.
Field Promotion (10 points)	Earn Rank 2 as a Marine.
Fire Drill (20 points)	Arm the emergency release and escape in under 2:30 on Sulaco Falls.
Game Over, Man! (30 points)	Complete all Campaign levels on any difficulty.
Heavy Lifting (20 points)	Defeat the Raven in under 1:10 on Soldier difficulty or higher.
I Can Handle Myself (40 points)	Purchase all Upgrades for a weapon.
I Feel Safer Already (10 points)	Have another player join your party.
I Heard THAT (25 points)	Collect all 12 Audio Logs.
I Like to Keep These Handy (30 points)	Collect all 6 Legendary Weapons.
I Love the Corps! (40 points)	Earn Rank 60 as a Marine.
It's a Dry Heat (20 points)	Kill 3 enemies with a single U4 Firebomb.
Just a Grunt (20 points)	Complete Hope in Hadley's.
Lean and Mean (20 points)	Earn Rank 20 as a Marine.
Let's Rock! (20 points)	Kill 10 Xenomorphs in a game with the M56A2 Smart Gun.
Love at First Sight (10 points)	Survive a Close Encounter with a Facehugger.
Majority Shareholder (25 points)	Spend 30 Commendations.
Micro Changes in Air Density (10 points)	Track 100 hostile targets with the Motion Tracker.
Mostly Come at Night... (20 points)	Find Newt's doll.
Need a Deck Of Cards? (5 points)	Set up a UA 571-C Remote Sentry.
No Need For Alarm (20 points)	Complete One Bullet without setting off the alarm.
No Offense (20 points)	Melee a Lurker that is pouncing towards you.
Not Bad For a Human (40 points)	Complete all Campaign levels on Hardened difficulty.
Oorah to Ashes (10 points)	Collect a Dog Tag.
Perfect Killing Machine (20 points)	Upgrade every Loadout slot for a Xenomorph class.
Personal Friend of Mine (10 points)	Collect a Legendary Weapon.
Quoth the Raven (20 points)	Complete The Raven.
Ready to Fry Half a City (5 points)	Edit a Marine Loadout.
Remember the Fallen (30 points)	Collect all 35 Dog Tags.
Secreted from What? (20 points)	Kill 5 Spitters without being damaged by acid.
Short, Controlled Bursts (20 points)	Defeat all Xenomorphs in the Sulaco hangar bay without them crossing your barricade.
State of the Badass Art (50 points)	Complete all Campaign levels on Ultimate Badass difficulty.
Stay Frosty (20 points)	Complete an entire Challenge category.
Still Got a Job to Do (20 points)	Complete Rampart.
Structural Perfection (5 points)	Edit a Xenomorph Loadout.
You Look Just Like I Feel (30 points)	Upgrade every Appearance slot once for your Marine.