Firefight: Chasm Ten
From Halopedia, the Halo wiki
Firefight: Chasm Ten
Firefight: Chasm Ten is an achievement in Halo 3: ODST. It is awarded for scoring over 200,000 points during a Firefight match on the map Chasm Ten. It is worth 10 Gamerscore.
This achievement is represented by an olive square with a Drone on it.
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