Here is the full list of Achievements for Halo Reach for the Xbox 360.
A Monument To All Your Sins (150 points) – Completed every mission in Halo: Reach alone, on Legendary
A New Challenger (10 points) – Completed all of the Daily Challenges in a given day
A Spoonful Of Blamite (10 points) – Killed 10 enemies in Firefight or Campaign with a supercombine explosion
A Storage Solution (5 points) – Used the File Browser to upload a file to your File Share
An Elegant Weapon (10 points) – Killed 10 enemies in a Firefight or Campaign session with the DMR
An Honor Serving (25 points) – Reached the rank of Captain in the UNSC
Banshees, Fast And Low (25 points) – Hijacked a Banshee during the Reach Campaign
Be My Wingman Anytime (5 points) – Let a teammate spawn on you 5 times in an Invasion Matchmaking game
Blaze Of Glory (25 points) – Scored 200,000 points in a Firefight game
Cool, File Bro (5 points) – Recommended a file to someone
Crowd Control (10 points) – Earned a Killionaire medal in Firefight
Doctor, Doctor (5 points) – Used a Health Pack to replenish life after taking body damage
Dust And Echoes (10 points) – Completed the 8th mission on Normal or harder
Firestarter (10 points) – Scored 50,000 points in a Firefight game
Folks Need Heroes… (50 points) – Completed the Campaign on Heroic difficulty
Game, Set, Match (25 points) – Completed a Firefight set on Legendary without dying
Gods Must Be Strong (125 points) – Completed the Campaign on Legendary difficulty
Heat In The Pipe (75 points) – Scored 1,000,000 points in a Firefight game
I Didn’t Train To Be A Pilot (10 points) – Killed 3 of the anti-aircraft batteries during the 8th mission
I Need A Weapon (10 points) – Completed the 4th mission on Normal or harder
I See You Favour A .45 (10 points) – Killed 10 enemies in a Firefight or Campaign session with the M6G pistol
If They Came To Hear Me Beg (25 points) – Performed an Assassination against an Elite to survive a fall that would’ve been fatal
Into The Howling Dark (10 points) – Completed the 7th mission on Normal or harder
KEEP IT CLEAN (5 points) – Killed 7 Moa during the 2nd mission of the Campaign
Knife to a Gun Fight (5 points) – As an Elite, killed 5 Spartan players in Matchmaking
Lemme Upgrade Ya (10 points) – Advanced a Commendation to a Silver state
Lucky Me (25 points) – Earned a Triple Kill while Jetpacking in Campaign, Firefight or Matchmaking
Make It Drizzle (10 points) – Purchased an item from the Armory
Make It Rain (10 points) – Purchased an item from the Armory that required the rank of Lt. Colonel
One Down, 51 to Go (10 points) – Completed a Weekly Challenge
Protocol Dictates Action (10 points) – Completed the 3rd mission on Normal or harder
Score Attack (10 points) – Scored 15,000 points in Score Attack Firefight Matchmaking
Send Me Out… With A Bang (10 points) – Completed the 10th mission on Normal or harder
Skunked (10 points) – Won a game of Invasion in the 1st phase
Swap Meet (10 points) – Traded weapons with an AI ally in Campaign
Tank Beats Everything (25 points) – Finished the 9th mission on Legendary with the Scorpion intact
That’s A Knife (10 points) – Performed an Assassination on an enemy
The Soldier We Need You To Be (25 points) – Completed the Campaign on Normal difficulty
The Start Of Something (15 points) – Reached the rank of Corporal in the UNSC
They’ve Always Been Faster (25 points) – Cleared the 2nd mission without setting foot in a drivable vehicle
This Is Not Your Grave (10 points) – Completed the 9th mission on Normal or harder
To War (10 points) – Completed the 5th mission on Normal or harder
Two Corpses in One Grave (25 points) – Killed 2 vehicles at once with the Target Locator in the 3rd mission
Wake Up Buttercup (25 points) – Destroyed the Corvette’s engines & escort in under 3 minutes in the 6th mission on Heroic or harder
We’re Just Getting Started (10 points) – Completed the 2nd mission on Normal or harder
What’s A Killing Spree? (5 points) – Earned a Killing Spree in multiplayer Matchmaking
Yes, Sensei (10 points) – Earned a First Strike Medal in a Matchmaking game
You Flew Pretty Good (10 points) – Completed the 6th mission on Normal or harder
Your Heresy Will Stay Your Feet (25 points) – Killed the Elite Zealot before he escaped during the 5th mission
Additionally, here are the latest achievements from the Noble Map Pack DLC:
Both Barrels (50 points) – Noble 1: Earn a Double Kill with the shotgun in multiplayer Matchmaking
Cross-Mappin’ (50 points) – Noble 1: Kill a player at long range with the DMR in a matchmade Slayer game
Offensive Driver (20 points) – Noble 1: Earn a kill in a matchmade Rocket Race game
Poppin’ & Lockin’ (25 points) – Noble 1: Destroy a vehicle using Armor Lock in a matchmade game
Totally Worth It (50 points) – Noble 1: Earn a Double Kill from the Grave in multiplayer Matchmaking
You Ate All the Chips (42 points) – Noble 1: Collect all of the flags in a matchmade Stockpile game
You Blew It Up! (13 points) – Noble 1: Blow up the research facility in a matchmade Invasion game on Breakpoint