Halo 3: ODST A.C.E.

From Halopedia, the Halo wiki

Halo 3 ODST tier 3.png

Halo 3: ODST A.C.E. is a career award found on the Xbox 360 version of Halo Waypoint.[1] It is represented by a skull and crossbones on a spade-shaped medal with a blue and black ribbon. The award consists of all 47 Halo 3: ODST achievements. The achievements are organized into three tiers.