One of the most iconic and game-shaping musical elements may be the main theme. It usually comes up in the main menu, when starting the game, so it is heard many times. It sums up the game’s emotional message and atmosphere, thus representing the entire soundtrack. Although not generally used with the same arrangement anywhere else, it has many brothers and sisters: the musical main theme finds its way into the soundtrack, interweaving the musical experience.
The idea has been used before.
The idea of a melody bestowing significance upon a piece of art has been used before. In European classical operas the “overture” has traditionally been composed at the end of the process, combining the significant elements and summing up all important ideas.
In Romanticism, the so called “Leitmotif” has been developed, which comes from German, meaning “leading motive”, lending identity to distinct elements and bringing them closer to the audience. Persons, items or even situations can be linked to a characteristic phrase or melody. The musical main-theme may be seen as an overall leitmotif of the whole piece.
Leitmotifs stay in our minds for years.
Some leitmotifs have gained huge popularity and stay in our minds for years. Jaws! leitmotif. Dagger-attack’s leitmotif from Hitchcock’s Psycho! Howard Shore’s Ring has multiple motifs: longing, deception, destruction. Jeremy Soule’s Dragonborn theme stands for dragon-power within the main character. Star Wars’ Force, the Dark Side, Darth Vader, Luke Skywalker … Indiana Jones, James Bond, Harry Potter, Jack Sparrow, Lord of the Rings, The Hobbit and many, many more.
The main-theme can change.
The main-theme as well as leitmotifs can change during the whole piece and come up in totally different suits. Variable instrumentation, other harmonizations, shifting moods and dynamics. For example, the hero’s theme could be timid and shy in the beginning and swell up to a bombastic hymn in the end of the game or movie (or opera).
In Civilization VI (2016), each tribe has its own simple melody and during the ages and the player’s progress from stone-age to atomic age the music changes, taking the tribe’s identity through many styles to a mighty hymn.
It is clear that a character’s outline can be more precise if completed by a musical idea. The same can be said for the whole game.