Definitely forgot about that, adding it into deckbuilding (sorry, been preoccupied with auction, come back, see "illegal decks" so on. Will refix.
Also, I don't think anybody else was doing that (I may be wrong), so I wasn't reminded of it.
Ok, reverted OP to what should have been the original post before I came in derping everything up. (I say should, since I used lazarus, and everything looks right).
Also, added that clause to deckbuilding section of rules.