The idea behind MR is a combination of Pokemon Stadium (although we must remind ourselves that this game was developed before the Nintendo license) and a virtual pet simulation, with a touch of the classic Commodore 64 game Mail Order Monsters thrown in for good measure. The gimmick involved with the game comes from the player's ability to use music CDs (in the guise of ancient arcane stone discs) to generate their monsters, with a different CD generally creating a very diverse creature each time. For example, by using the Chemical Brothers' Surrender it created a small tentacle-like creature that was pink in hue, very fast but not all that strong. The Corrs' Forgiven not Forgotten spawned a large white ape with a golden mane of hair who enjoys eating mangos, which was very strong but slow.

After you have created your monster (or you can just buy a pre-made one from the market if you don't own any CDs), it then becomes your job to train it to become the best arena fighter possible. You choose what the monster will eat, when it gets to sleep, and what kind of training drills it must do in order to increase it's many fighting abilities including dodge, power and mind strength. Monsters can even be joined with another to make a bigger, more powerful creature. The basic aim of the game is to design a monster so good that he or she will go on to win the many tournaments on offer and therefore bestow on you the title of the greatest monster rancher of all time.