The two-headed monster card is considered to be one of just six in existence, and as such, it comes with a high price tag
When picking cards, you cannot use more than 4 of the same card, with the exception of basic energy cards
It may seem obvious which belongs to which Pokmon set, but in the original Black and White video games, Reshiram was only catchable in Black, Zekrom in white
Blue will get four +1/+1 counters as well as Flying, Vigilance, Trample, and Lifelink
They did not specify holos, but just each card
One player ran the numbers and suggested completing the entire expansion without paying anything would take something between approximately 500 and 1100 days of consecutive play on average, depending on what in-game rewards and mechanics you factor into the equation