As most of the evolutions between Myst and Riven, the latter’s music is more elaborate than the former’s. It’s also significantly more sinister in tone, with slower, more furtive orchestrations and ghostly, haunting melodies, which have the common distinction of having been created by using a mix of real instruments and synthesizers. All in all, it enhances the constant impression of being watched that the game establishes from the outset and contrasts rather forcibly with the bright sunny weather reigning over the age. It also makes many indoor sojourns significantly tenser.
Each of the three main characters has their own theme, but each shares the ghostly unease that pervades the rest of the soundtrack. They are also intimately interconnected, with each other and with some of the game’s other tracks, creating a feeling of cohesion, like Sirrus’ and Achenar’s themes did in Myst. Although here, the cohesion sometimes rises to the extent of uniformity, and it becomes difficult to tell the tracks apart, which is rather unfortunate. Still, considering the overall atmosphere is effectively creepy, it does work.
Catherine’s is the weakest theme of the three, as it’s barely more than an ambience; it does, however, have a more successful incarnation as “Catherine’s Prelude”, the somewhat hypnotic-sounding theme for Prison Island, which also borrows some sonorities from Atrus’ theme. The latter is more distinctive: it opens the game and notably features a slightly modified version of the Myst Theme from the first game, although, for such a positive character, it’s almost unsettling how chilling it sounds. Gehn’s theme, however, takes the cake, perhaps unsurprisingly so. It’s the most distinctive and the most menacing of the three, with its insistent base line and eerie oboe-like strains (this is actually supposed to be the instrument hanging in his bedroom on the 233rd Age: a maral-obe). It also echoes through many other tracks, although it sometimes shares the stage with leitmotifs from Atrus’ theme (e.g. the Survey Island Theme, “Jungle Totem”, which plays in the vicinity of the Wahrk statue on Jungle Island; “Gateroom”, the beetle room music; or “Fissure”, the game’s closing track). The effect is not only an impression of Gehn’s stranglehold over Riven, but also one of conflict between Gehn and Atrus, which is eminently appropriate to the game’s theme.
The Moiety also have their own theme, which is another highlight of the soundtrack. It appears under several guises in Moiety-related areas (e.g. “Moiety Caves”), and “Catherine’s Freedom” is its most spectacular incarnation. The Wahrk room theme from Survey Island and “The Red Cave”, which serves as the buildup for it, create a monumentally creepy atmosphere, and the Temple theme from Temple Island distils a strangely appealing mix of Asian sonorities and Egyptian-looking surroundings. Overall, I think this illustrates the idea behind the entire soundtrack, as stated by its composer, Robyn Miller: a feeling of something familiar, yet strange.