Like the previous installments, this game involves the raising, breeding, and fighting of monsters. Monsters are created via a "Saucer Stone" regeneration system. There are several methods to obtaining a monster. Players must go to the Shrine, where they can choose their preferred method to generate a monster. One is the disc method where the player swaps the Monster Rancher 4 disc with a CD, DVD, or another game disc. A monster is then generated from the data contained on that disc. The next method is through in-game disc stones. Which can be obtained from adventures or tournaments. A pre-determined monster will then be generated based on the specific disc stone. Once the monster has been generated, their data is recorded in the encyclopedia. Players can then regenerate any monster that has been recorded in the encyclopedia at any point. Once a player regenerates a monster, they can raise it on a ranch, and train it to compete in battles. The limit for monsters depend on the size of their ranch but the maximum is five monsters.