This article is about the campaign achievement. For other uses, see Alpha Site (disambiguation).
ONI Alpha Site
ONI Alpha Site is an Achievement in Halo 3: ODST awarded for completing the Campaign mission ONI Alpha Site on normal or above and unlocks the Alpha Site map for Firefight. It is worth 30 Gamerscore.[1]
It is represented by an olive circle, with the Marathon symbol imprinted in it, with the remote detonator for an M165 Demolition Charge in front of it.
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