Sativa Dominant Alaskan Thunder Fuck (also referred to as ATF, Matanuska Thunder Fuck or Matanuska Tundra) is a legendary sativa marijuana strain originating in the Matanuska Valley area of Alaska. According to the legend, it was originally a Northern California sativa crossed with a Russian ruderalis, but sometime in the late 70s it was crossed with Afghani genetics to make it heartier (and also making it a hybrid).