Good Samaritan
From Halopedia, the Halo wiki
Good Samaritan
Good Samaritan is an Achievement in Halo 3: ODST. It is awarded for not killing any Engineers during a full campain runtrough,[1] in single player or Co-op. It is worth 20 Gamerpoints.[2] This achievement will unlock the full ODST Ballistic Battle Armor for your Xbox Live avatar on Halo Waypoint.[3]
It is represented by an ODST helmet looking upwards shown in a white light.
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