Trophy is a new type of master card. A trophy may be put into play using a master phase action (or can be retrieved as listed under "Red List"). It has no effect until it is moved to a vampire.
When any vampire burns a Red List minion in combat or as a (D) action (including diablerie), the controller of the trophy may choose to move the trophy to that vampire. Any number of trophies in play may be moved to the vampire in this way. Once placed on a vampire, a trophy cannot be moved again.
See the Red List rule for more about playing Trophies.