Cheers for that Wildfire.
I picked them up from a gaming shop (Games World) a while ago. There was a bunch in the display cabinet and from memory I had read somewhere that cards from Starter and Portal had just become legal so I bought all they had (and got a discount to boot). Originally my idea was to try to get the full set but ended up keeping them unopened just in case they went up in value. I got a box or two of Ice Age, Fallen and Homelands which haven't done nearly so well..