There are only 15 cards in the decklist that are colorless, and 52 that are white and will be affected by Pearl Medallion
Essentially, they can be reduced to: Lacking haste means she is vulnerable to removal and board wipes As a six-mana creature, she can be increasingly hard to keep in play Since she is capable of one-shotting an opponent, shes often a magnet for removal In my original build, I used cards like Bloodsworn Steward, Swiftfoot Boots, and Sword of Vengeance as extra ways to grant haste
It was released as four Commander decks, but also had Collector Boosters that included special art treatments and the potential for Surge Foils and Extended Arts
Having fetches and shocks for that tiny period between M15 and "Huey" would not ruin standard
Here's how this combo works: Control Phyrexian Altar, Blood Artist or another dork with a similar ability, a Zombie