The Liberty Pass is a Key item introduced and used within Generation V. It grants permission to board the ship docked at the Liberty Pier in Castelia City, which leads to Liberty Garden and the legendary Pokémon Victini. It is the only Unova based event item. When you arrive at the western pier of Castelia City, a sailor will offer to take you to Liberty Garden. If you do not have the Liberty Pass with you, the sailor will refuse your entry.