Master your class, with Mastery Pack Guardian, the first in a new booster set series focused on class affinity. Mastery Packs are also designed for Crack, Shuffle, Play! , the fastest, funnest, easiest way to play Flesh and Blood! Simply crack 3 packs, remove the last 3 cards of each pack, shuffle the rest, and play!Mastery Pack Guardian is a booster set featuring 130 cards, including the anticipated arrival of Valda, Seismic Impact for Classic Constructed.