Halo 3: ODST achievements

Halo 3: ODST

3.9 from 15666 votes

There are a maximum of 47 Halo 3: ODST achievements worth 1,476 (1,000)

187,192 tracked gamers have this game, 18,408 have completed it (9.83%)

Achievement Details

ONI Alpha Site in Halo 3: ODST

ONI Alpha Site35 (30)

Complete ONI Alpha Site on Normal, Heroic, or Legendary to unlock a new Firefight mission.

  • Unlocked by 138,821 tracked gamers (74% - TA Ratio = 1.15) 187,192  

Achievement Guide for ONI Alpha Site

71,648 (42,223)
Achievement won on 22 Sep 09
TA Score for this game: 1,476
Posted on 22 September 09 at 20:53
This solution has 15 positive votes and 13 negative votes. Please log in to vote.
You must play on Normal, Heroic or Legendary. It cannot be missed from normal story progression. I recommend playing on Legendary (solo or with a buddy) straight through for your first play through.
Please log in to comment on this solution.
Do you have a question about this achievement? Please post it in the Halo 3: ODST Forum