Civilization 6 has dynamic themes for each civilization - as you progress forward in time and technology, the backing theme of your civilization will change. This is Russia’s theme after reaching the Atomic era, and is one of the best examples of the dynamic soundtrack in my opinion.
I didn’t know it at the time, but hours and hours of exposure to this theme during car rides would implant within me an innate appreciation for what video game music specifically tries to do, and the limitations it tries to do it within....