Complex sentence: Krampus is heard landing on their roof, and lights begin to flicker the remaining family members quickly decide to make a run for the snowplow only to find it doesn't work.
Split into simpler sentences: Krampus is heard landing on their roof, and lights begin to flicker the remaining family members quickly decide to make a run for the snowplow. The rest of the family manages to reach the snowplow only to find it doesn't work.