Killed Vehicle is a medal achieved for destroying a vehicle in Halo 3. It resembles the Stunned achievement medal. It is represented by a gray cross with a do not enter sign without text embedded in it.
While developing the Halo games, Bungie, 343 Industries and Ensemble Studios have had to cut some content, such as vehicles, gameplay, and story elements, from the final products. Much of this content has been confirmed by videos and commentary in special edition DVDs, interviews with developers, and released concept art.