Keeper of the Crown // Coronation of the Wilds

If an effect instructs you to choose a card name, you may choose the alternative Adventure name. Consider only the alternative characteristics to determine whether that is an appropriate name to choose.

For many playtest cards, you’ll need to make a generous assumption that basic game rules would be updated to allow them to work. The Mystery Booster 2 Playtest Card Notes section (reproduced here in individual Gatherer rulings) provides guidance for fitting these cards into the existing rules structure.

Due to its color indicator (appearing to the left of its type line), Keeper of the Crown is green. Color indicators apply in all zones, not just the battlefield.

If you cast an adventurer card as an Adventure, use only its alternative characteristics to determine whether it’s legal to cast that spell. For example, if you control Elsha of the Infinite (“You may cast noncreature spells from the top of your library”) and Keeper of the Crown is on top of your library, you can cast Coronation of the Wilds, but not Keeper of the Crown.

A “legendary source” is a permanent, spell, or card in any zone with the supertype “legendary.” Notably, a creature that becomes legendary due to Coronation of the Wilds is a legendary source.

If an effect copies an Adventure spell, that copy is exiled as it resolves. It ceases to exist as a state-based action; it’s not possible to cast the copy as a permanent.