Complex sentence: Blake shot and killed her, but he carried the disfiguring scar she left, running from his right eye to the corner of his mouth; after this incident, he wore a leather gimp-style mask when dressed as The Comedian.
Split into simpler sentences: Blake shot and killed her, but the attack left his face permanently disfigured with a scar running from his right eye to the corner of his mouth. After this incident, he began wearing a leather gimp-style mask when dressed as the Comedian.