Complex sentence: As Gerald was walking back he saw one of the victims move (later revealed as Kippi Vaught) because the bullet had only grazed her skull, Gerald returned and shot her three more times in the head killing her.
Split into simpler sentences: As Gerald was walking back he saw one of the victims move (later revealed as Kippi Vaught) because the bullet had only grazed her skull. He returned and shot her three more times in the head, killing her.