The Bands of New York expansion is played by replacing the New York bot with an actual player, which brings the allowed number of players up to 5. The more the Heroes will make noise, the more cards New York will be able to play - and the stronger they will be.
New York doesn't play with mission cubes like the bot: it will use mission cards instead, trying to resolve some missions' requirements, triggering events in the game like destroying the gullfire or discarding a timer tile, approaching victory.