One of the only things I can think of that came up was my Inquisitor along side my Dark Angels.He and his storm troopers used the Valkyrie (which I guess I can't now.Grr!) He couldn't use anything else, nor any other unit use the Valkyrie. The Special Character had some kind of rule to him about transports ,but other than that nothing else could use stuff, even if same player and list.