The most valuable of the bunch is the one found as part of the Prize Pack Series
The contrast between the pure white backdrop and the fine details of Reshirams form creates a card that feels simultaneously sacred and potent a beacon of legendary status amid the sets monochrome aesthetic
Here's a rough breakdown based on the default configuration (13 cards/batch, 20 batches/set) and approximate API pricing at the time of writing
Gelatinous Cube This kind of effect was first introduced on Faceless Butcher, and since Gelatinous Cube is a much better version of it, its the one that will be part of this list
9 Fable Of The Mirror-Breaker, Reflection Of Kiki-Jiki One of those obvious-in-retrospect power cards that many overlooked upon its initial reveal, Fable of the Mirror-Breaker has gone on to play key roles in Midrange decks in Standard, Pioneer, Modern, and even Legacy
The highlight is the debut of Raging Bolt ex, an ancient ancestor of Raikou, whose majestic and thunderous presence is captured in stunning detail