Core rule · Rules Tome 2.0.8 § 406
Banish zone
Banished cards are public but outside play and the discard pile.
How it works
Full rule
A card goes to its owner’s banish zone only when an action or effect says to banish it. Banished cards are visible to all players and are not in play.
At the table
Example
A character banished instead of killed does not create death or kill Reacts.
Watch for this
Common mistake
Banish is not another word for discard or destroy; effects that search the discard pile cannot select a banished card.