Neptune uses 1-2 decks of regular playing cards. You also need a trident (search for a 3-tined fork) and the crown included. The Starting player plays some cards from his hand which must be all the same kind, but any number of them. The other players then in turn lay down cards which try to beat his. The winner takes all the cards. The Crown and the Trident are gained in special ways and have special powers for use during the game.