Is it because theyre super special, vanishingly rare, almost legendary in their scarcity
Zur's Weirding has a nice mix of design elements
Notably, because Riku can copy creatures that enter even if they werent cast, Sneak Attack and other cards that let you bypass enormous casting costs make for strong additions
Limit one pouch per player
In fact, pretty much everyone who's anyone has at least one card in this Universes Beyond set, and in some cases several, to reflect how they changed throughout the adventure
Collector Boosters / Booster Display Full of rares, foils, and special treatmentsrebuild the Multiverse while building up your collection in this conclusion to the March of the Machine storyline