“The Blue Diamond” is about a group of children playing a game where you can have some adventures. The player comes to town as a new kid and has to help his new friends to win the game. The aim of this game is to steal a diamond from the opposing team and bring it back to your own camp, when you have achieved that, you have won. In free play, the player can play for money in the casino and deposit it in the bank in the city.

As the story progresses, two different cities and other interesting places will be discovered and explored. There are no limits to the children's imagination, so you can transform yourself into an animal or an insect with the help of magic potions, in order to be able to see in the dark or to come through small openings. There are numerous weapons to buy and skills to learn that will help you defeat your opponents.