From the post:
This K-9 figure is a special promotional expansion that will be added to the first print run of Doctor Who: Time of the Daleks. The expansion includes one K-9 model and a rule card that explains how to use him in your games. Make sure you pre-order your copy of the game now to secure your own K-9 promo.
K-9 adds an interesting element to the game, allowing players to re-roll a single story die each turn. It’s up to the player who had K-9 last to make sure he goes to whichever Doctor most needs his help.