Lucius first fought against Kate with the assistance of Ben. He neither sustained nor caused any real injuries, and abandoned Kate to attack Dorcas as soon as he saw her. They had a short but brutal battle, where he sustained a smashed left arm, a head wound, several burns, and got turned into a half-insect complete with antennae. Dorcas then stunned him and left him on the ground, which is where Narcissa fortunately found him and effectively saved his sorry arse.