During your control phase, fire your AT-AT Cannon (if within range of the Main Power Generators) as follows:
Prepare To Target The Main Generator: Draw destiny.
Maximum Firepower!: If (destiny + X + Y) > 8, Main Power Generators site is "blown away" and this card is lost. Otherwise this card is used.
X = ability of one of AT-AT's pilots.
Y = total Hoth sites you control.