My friend has alk the sets theyve releaced so far. The added mechanics make the game more fun, set 4 is a pirate set, gives you the option to play on a pirate ship, adds a sea deck in the middle and when its time to flip a card on the sea deck, the effects, effect everybody. Simular mechanic with set 6 the villian set where you can play in the dungeon, same set up as sea events except dungeon event. Or yoy can set up where a teleportaion spell has gone arwry, and your transported between the sea and dungeon. Added mechanics add more ways to play, and add differnt levels of challenge.