They came out of nowhere. One minute the AT-ST's in our support squadron had guns blazing and we were advancing at quite a rapid pace, and the next all of the AT-ST's were minus one leg and our platoon had been transformed into a squad.-Unknown Imperial stormtrooper The Sahharran D-90 Ground Assault Drone was a droid designed to combat the threat of the Imperial AT-AT, as well as turrets, large groups of infantry, and tanks.