Sea Hag

If an adventurer card ends up in exile for any other reason than by exiling itself while resolving, it won’t give you permission to cast it as a permanent spell.

An adventurer card is a permanent card in every zone except the stack, as well as while on the stack if not cast as an Adventure. Ignore its alternative characteristics in those cases. For example, while it’s in your graveyard, Altar of Bhaal is an artifact card whose mana value is 2.

If an object becomes a copy of an object that has an Adventure, the copy also has an Adventure. If it changes zones, it will either cease to exist (if it’s a token) or cease to be a copy (if it’s a nontoken permanent), and so you won’t be able to cast it as an Adventure.