You'll want to move as many characters to that location as possible , prioritizing characters with Reckless challengers, low Willpower questers like Simba, Scrappy Cub, and, if you can find her, Moana, Born Leader, who will ready all your other location-bound characters every time she quests
(1) Secret victory card
I could see why the crossover was beneficial for Magic , since Final Fantasy is a hugely popular gaming franchise, and I wouldnt be surprised if the two properties share some of their fanbase
The fact that the rarities are fixed makes them balanced for Limited play, while other boosters (set boosters, collector boosters) arent
The answer that Adventures in the Forgotten Realms found is a gameplay mechanic called Venture