Imperial tactics are typically founded on shocking and terrifying the enemy, a goal that often pre-empts force protection or efficiency. It is this tactical philosophy that gave rise to the AT-AT. Huge, heavily armored and slow moving, these awesome vehicles are impervious to most weapons fire, but there are several easily exploitable flaws that the Rebellion has used to bring them down. Despite this, Imperial walkers have proven quite effective; few forces in the galaxy can mount an effective defense for long against a full AT-AT assault.