I see that the KD Sci-Fi Twilight Knight that includes two KD:Monster game cards is going for 30-40 bucks on Ebay: Don't buy it.
CMON still has it in stock for 15 bucks plus shipping- still over 70 units available. Since I'm impatiently waiting the delivery of KD:Monster, I went ahead and scooped a Knight up myself- you should too.
Edit: Kingdom Death: Monster is up for pre-order on Poots website. After shipping (inside US) the game comes to 320.00 bucks- quite a steal to the 400-500 bucks trending on ebay just hours before pre-orders were opened. The investment is heavy (almost an entire army equivalent in most game systems), but, justifiable for the sheer amount of content you receive.Get it while you can!