Trash and recovery

Deleting something in EON isn't final: removed decks and cards go to their Deck Pack's Trash.

Recover

Open the Trash from the pack's sidebar, pick what you want to restore, and it returns to where it was, review history intact.

Permanent deletion

From the same Trash you can delete content permanently. That action is irreversible, so the app asks you to confirm.

Review history is valuable: when in doubt, leave things in the Trash.