Complex sentence: These markings suggest that the devil is most active at dawn and dusk, and they are thought to focus biting attacks to less important areas of the body, as fighting between devils often leads to a concentration of scars in that region.
Split into simpler sentences: These markings suggest that the devil is most active at dawn and dusk. These marks are thought to focus biting attacks to less important areas of the body, as fighting between devils often leads to a concentration of scars in that region.