We can expect the value of showcase cards to be at least 30% more expensive than the normal version, and thats being conservative
This is especially true if you dont already have three total lands to flash it back on turn 3
Plus, whenever one or more creature cards hits your graveyard from your library, you get to create a 2/2 Zombie token
Using an indestructible creature to block a lifelinker will still result in the opponent gaining life, and blocking a creature with wither will still cause -1/-1 counters to be placed on your creature (which could actually kill it!)
Premium foil cards are randomly inserted
Speaking from the uninformed perspective of someone who's never opened an Unfinity pack, the set looks like it would be fun the first time you tried it, and then never again (outside of an Attraction Commander deck, which admittedly sounds like a laugh)