Spells and abilities that were targeting that permanent and Auras and Equipment that were attached to that permanent aren't affected unless the new characteristics of the object change the legality of those targets or attachments
Challenger decks are 60-card decks that are designed for play in a format called Standard
Go get your Nykthos, Shrine to Nyx
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Although no information has been provided yet on what cards will be included in the decks, they will likely end up being the same or similar to many of the Disney Lorcana Starter Decks that are already available
What if we printed a slower Birthing Pod that counts colors and you get to cast them from Exile instead of making them enter for free sounds like just the right amount of hoops to jump through to make the card not an auto include in every deck