A medium balance can be built in the Elemental balance space of the Games room in a player-owned house. It requires 57 Construction to build and when built, it gives 252 experience. The player must have a hammer and a saw in their inventory to build it.
To play the game, there must be two players. Each player has a turn at turning the sphere to the colour white, which means it has balanced with all of the elements. Using higher-level spells on it, such as Fire Wave, will make the sphere more of the element's colour than a lower-level spell, such as Fire Strike. Using this can help in turning the sphere white. To change the sphere white, you cast the spells that begin to balance it. If it is slightly green, perhaps you should not use any Earth-based spells.