There is a total of 20 different bonus cards available that vary in value, and each one has the same odds of showing up in your product
Because this includes all forms of Artifacts, it usually means youll end up with a powerful flying army too
(8/25/2017) To activate Inalla's last ability, you may tap any untapped Wizards you control, including ones you haven't controlled continuously since the beginning of your most recent turn, such as Inalla itself
And I do think they've managed to do that pretty well
Pokmon card prices can fluctuate wildly, so it's impossible to put a concrete figure on the cost of any one card
Pokebeach mentions that these cards are worth around $36 and $39, depending on which Pokmon is portrayed and the market fluctuations