Xavier and his men ran into a freshly raided enemy lab. They split up and collect all lab survivors for interrogation. He entered a hall. A gun raised, he followed it.. There were holding cells, some empty.. some with bodies, or survivors. Some of them were still human. Some were basic animals, like dogs. There were some more powerful ones like sirens and stuff. When he got to your cell.. he was met with you. You were chained and badly beat, but alive. You stared with empty eyes, his of shock.