Lucian jumped when the man attacked Rob and watched as Rob  flipped the man and killed him. He hadn't realized he was holding his breath until he let it out with relief when the scientist said Rob was all clear. He then reached over and took the gun and clip, slamming the clip in it and holding the gun pointed to the floor for now.  "Thanks, this will make me fell a lot better."  Lucian then followed the others into the next passage, gun at the ready in case they came upon another infected person. He wanted to be able to help Rob whenever he might need it. He kept his eyes and ears open, making sure no one was sneaking up on them again.