Il sito achieve360points è venuto in possesso di ben 49 obiettivi sbloccabili che saranno presenti nell'attesissimo Halo 3. Da questi scopriamo che la campagna prevederà nove missioni, sicuramente suddivise in più livelli come nei precedenti capitoli. Molti obiettivi riguardano poi la modalità multiplayer, ed inoltre scopriamo la possibilità di giocare le missioni della campagna in una misteriosa modalità chiamata "meta-game": cosa significherà? Di seguito l'elenco completo degli obiettivi rivelati.

1. Landfall Finish the first mission of the Campaign on Normal, Heroic, or Legendary.	20 punti
2. Holdout Finish the second mission of the Campaign on Normal, Heroic, or Legendary.	20 punti
3. The Road Finish the third mission of the Campaign on Normal, Heroic, or Legendary.	20 punti
4. Assault Finish the fourth mission of the Campaign on Normal, Heroic, or Legendary.	30 punti
5. Cleansing Finish the fifth mission of the Campaign on Normal, Heroic, or Legendary.	30 punti
6. Refuge Finish the sixth mission of the Campaign on Normal, Heroic, or Legendary.	30 punti
7. Last Stand Finish the seventh mission of the Campaign on Normal, Heroic, or Legendary.	40 punti
8. The Key Finish the eighth mission of the Campaign on Normal, Heroic, or Legendary.	40 punti
9. Return Finish the final mission of the Campaign on Normal, Heroic, or Legendary.	50 punti
10. Campaign Complete: Normal Finish the Campaign on Normal.	125 punti
11. Campaign Complete: Heroic Finish the Campaign on Heroic (unlocks achievement for Normal, if not earned).	125 punti
12. Campaign Complete: Legendary Finish the Campaign on Legendary (unlocks achievements for Normal and Heroic, if not earned).	125 punti
13. Iron Finish the Campaign on Normal, Heroic, or Legendary, then find and claim this skull.	10 punti
14. Black Eye Finish the Campaign on Normal, Heroic, or Legendary, then find and claim this skull.	10 punti
15. Tough Luck Finish the Campaign on Normal, Heroic, or Legendary, then find and claim this skull.	10 punti
16. Catch Finish the Campaign on Normal, Heroic, or Legendary, then find and claim this skull.	10 punti
17. Fog Finish the Campaign on Normal, Heroic, or Legendary, then find and claim this skull.	10 punti
18. Famine Finish the Campaign on Normal, Heroic, or Legendary, then find and claim this skull.	10 punti
19. Thunderstorm Finish the Campaign on Normal, Heroic, or Legendary, then find and claim this skull.	10 punti
20. Tilt Finish the Campaign on Normal, Heroic, or Legendary, then find and claim this skull.	10 punti
21. Mythic Finish the Campaign on Normal, Heroic, or Legendary, then find and claim this skull.	10 punti
22. Spartan Program Recruit Win your first game in matchmaking to sign up for the Spartan Program (Online).	10 punti
23. UNSC Spartan Earn your Sergeant rating to be recognized as a true Spartan (Online).	15 punti
24. Spartan Officer Advance to the Spartan Officer ranks (Online).	25 punti
25. Two for One Score a Double Kill with a single spartan laser shot in a ranked free for all playlist (Online).	5 punti
26. Too Close to the Sun Destroy an enemy banshee with the spartan laser or missile pod in a ranked playlist or in campaign.	5 punti
27. Triple Kill Kill 3 enemies within 4 seconds of one another in a ranked free for all playlist (Online).	5 punti
28. Overkill Kill 4 enemies within 4 seconds of one another in a ranked free for all playlist (Online).	5 punti
29. Lee R Wilson Memorial Score 5 grenade sticks in any ranked free for all playlist (Online).	5 punti
30. We’re in for some Chop Destroy an enemy vehicle with equipment in a ranked playlist or in campaign.	5 punti
31. Killing Frenzy Kill 10 enemies without dying in any ranked free for all playlist (Online).	5 punti
32. Steppin' Razor Score a Triple Kill with the sword in a ranked free for all playlist (Online).	5 punti
33. Mongoose Mowdown Splatter an enemy with the mongoose in a ranked free for all playlist (Online).	5 punti
34. Up Close and Personal Kill 5 enemies by melee or assassination in a ranked free for all playlist (Online).	5 punti
35. Fear the Pink Mist Kill 5 enemies with the needler in a ranked free for all playlist or in campaign.	5 punti
36. Headshot Honcho Kill 10 enemies with headshots in a ranked free for all playlist or in campaign.	5 punti
37. Used Car Salesman Destroy a vehicle that has three enemies in it in a ranked playlist or in campaign.	5 punti
38. Marathon Man Locate and access all Terminals in the Campaign.	40 punti
39. MVP Earn the MVP in any ranked playlist (Online).	5 punti
40. Maybe Next Time Buddy Board the same vehicle within 10 seconds after being boarded in any free for all playlist (Online).	5 punti
41. Demon Score over punti in the Campaign meta-game on the second mission.	10 punti
42. Guerilla Score over punti in the Campaign meta-game on the first mission.	10 punti
43. Cavalier Score over punti in the Campaign meta-game on the third mission.	10 punti
44. Askar Score over punti in the Campaign meta-game on the fourth mission.	10 punti
45. Exterminator Score over punti in the Campaign meta-game on the fifth mission.	10 punti
46. Ranger Score over punti in the Campaign meta-game on the sixth mission.	10 punti
47. Vanguard Score over punti in the Campaign meta-game on the seventh mission.	10 punti
48. Orpheus Score over punti in the Campaign meta-game on eighth mission.	10 punti
49. Reclaimer Score over punti in the Campaign meta-game on the final mission.	10 punti