- Demon
Score over 15,000 points in the Campaign meta-game on the second mission.
18 May 2010 - 4 guides
- Guerilla
Score over 15,000 points in the Campaign meta-game on the first mission.
16 May 2010 - 5 guides
- Landfall
Finish the first mission of the Campaign on Normal, Heroic, or Legendary.
Unlocked offline - 1 guide
- Fear the Pink Mist
Kill 5 enemies with the needler in a ranked free for all playlist or in campaign.
Unlocked offline - 6 guides
- Spartan Officer
Advance to the Spartan Officer ranks (Online).
02 May 2010 - 8 guides
- Reclaimer
Score over 15,000 points in the Campaign meta-game on the final mission.
22 December 2009 - 4 guides
- Ranger
Score over 50,000 points in the Campaign meta-game on the sixth mission.
22 December 2009 - 6 guides
- Marathon Man
Locate and access all Terminals in the Campaign.
22 December 2009 - 9 guides
- Tilt
Find and claim this skull when playing on Normal, Heroic or Legendary difficulty.
22 December 2009 - 4 guides
- Thunderstorm
Find and claim this skull when playing on Normal, Heroic or Legendary difficulty.
22 December 2009 - 2 guides
- Catch
Find and claim this skull when playing on Normal, Heroic or Legendary difficulty.
22 December 2009 - 5 guides
- Campaign Complete: Legendary
Finish the Campaign on Legendary (unlocks achievements for Normal and Heroic, if not earned).
22 December 2009 - 17 guides
- Campaign Complete: Heroic
Finish the Campaign on Heroic (unlocks achievement for Normal, if not earned).
22 December 2009 - 2 guides
- Campaign Complete: Normal
Finish the Campaign on Normal.
22 December 2009 - 1 guide
- Return
Finish the final mission of the Campaign on Normal, Heroic, or Legendary.
22 December 2009 - 1 guide
- The Key
Finish the eighth mission of the Campaign on Normal, Heroic, or Legendary.
22 December 2009 - 1 guide
- Mythic
Find and claim this skull when playing on Normal, Heroic or Legendary difficulty.
21 October 2009 - 3 guides
- Refuge
Finish the sixth mission of the Campaign on Normal, Heroic, or Legendary.
30 September 2009 - 1 guide
- Last Stand
Finish the seventh mission of the Campaign on Normal, Heroic, or Legendary.
28 September 2009 - 2 guides
- Used Car Salesman
Destroy a vehicle that has three enemies in it in a ranked playlist or in campaign.
07 September 2009 - 7 guides
- Cleansing
Finish the fifth mission of the Campaign on Normal, Heroic, or Legendary.
07 September 2009 - 1 guide
- Famine
Find and claim this skull when playing on Normal, Heroic or Legendary difficulty.
03 September 2009 - 5 guides
- Fog
Find and claim this skull when playing on Normal, Heroic or Legendary difficulty.
02 September 2009 - 4 guides
- Assault
Finish the fourth mission of the Campaign on Normal, Heroic, or Legendary.
02 September 2009 - 1 guide
- The Road
Finish the third mission of the Campaign on Normal, Heroic, or Legendary.
02 September 2009 - 1 guide
- Tough Luck
Find and claim this skull when playing on Normal, Heroic or Legendary difficulty.
02 September 2009 - 3 guides
- We’re in for some Chop
Destroy an enemy vehicle with equipment in a ranked playlist or in campaign.
13 May 2009 - 3 guides
- Too Close to the Sun
Destroy an enemy banshee with the spartan laser or missile pod in a ranked playlist or in campaign.
10 May 2009 - 4 guides
- Mongoose Mowdown
Splatter an enemy with the mongoose in a ranked free for all playlist (Online).
10 May 2009 - 9 guides
- Headshot Honcho
Kill 10 enemies with headshots in a ranked free for all playlist or in campaign.
06 May 2009 - 4 guides
- Lee R Wilson Memorial
Score 5 grenade sticks in any ranked free for all playlist (Online).
28 February 2008 - 8 guides
- Triple Kill
Kill 3 enemies within 4 seconds of one another in a ranked free for all playlist (Online).
27 February 2008 - 6 guides
- Holdout
Finish the second mission of the Campaign on Normal, Heroic, or Legendary.
27 February 2008 - 1 guide
- Black Eye
Find and claim this skull when playing on Normal, Heroic or Legendary difficulty.
27 February 2008 - 3 guides
- UNSC Spartan
Earn your Sergeant rating to be recognized as a true Spartan (Online).
27 February 2008 - 2 guides
- Up Close and Personal
Kill 5 enemies by melee or assassination in a ranked free for all playlist (Online).
27 February 2008 - 2 guides
- MVP
Earn the MVP in any ranked playlist (Online).
26 February 2008 - 3 guides
- Iron
Find and claim this skull when playing on Normal, Heroic or Legendary difficulty.
25 February 2008 - 3 guides
- Graduate
Earn 5 EXP or finish 10 games to complete the requirements for basic training (Online).
25 February 2008 - 4 guides
- Save This Film
On a Mythic map, get a Perfection medal during any ranked or social match.
11 May 2010 - 9 guides
- Have Fun Respawning
On a Mythic map, get an Extermination during any ranked or social match.
02 May 2010 - 6 guides
- Killtacular
On a Mythic map, get a Killtacular during any ranked or social match.
01 May 2010 - 11 guides
- Post Mortem
On Orbital, get 2 Death From the Grave medals during any ranked or social match.
27 October 2009 - 10 guides
- Sandbox Skull
On Sandbox, find the hidden skull.
08 May 2009 - 10 guides
- Orbital Skull
On Orbital, find the hidden skull.
08 May 2009 - 5 guides
- Assembly Skull
On Assembly, find the hidden skull.
08 May 2009 - 4 guides
- Hammer Time
On Assembly, get 5 Hammer kills during any ranked or social match.
08 May 2009 - 4 guides
- Tank Dropper
On any Mythic map, get a kill on another player while in monitor mode.
08 May 2009 - 13 guides
- Awww, Too Bad
On a Mythic map, get a Killjoy medal during any ranked or social match.
07 May 2009 - 2 guides
- … Get the Horns
On a Mythic map, get a Bulltrue medal during any ranked or social match.
07 May 2009 - 14 guides
- Delicious Brains
On a Mythic map, infect 2 humans during any ranked or social match.
07 May 2009 - 2 guides
- Zombie Repeller
On a Mythic map, kill 2 Zombies during any ranked or social match.
07 May 2009 - 2 guides