pianos and their role in susie's music
the reason there's some merit in discussing this is because in chapter 4, susie reveals what the piano actually means to her: it's a painful reminder of a childhood event that left a deep scar in her sense of belonging and self-worth.
in other words, the piano is tied to the parts of her that she doesn't show others, such as her loneliness or her vulnerability
and toby displays this through her music. take, for example, the eponymous 'susie' theme:
it's a straightforward track with an electric guitar that riffs over a somber piano bass line. taking what we've said above, i personally think this is a perfect window into susie as a character: someone putting up a bravado and a tough act (electric guitar) while harboring a deep loneliness (piano). even without context of her character, you can feel the tension of the guitar compared to the lonely cries of the piano.
'vs susie' builds on susie's theme, with the electric guitar giving it a menacing start. another guitar layers onto the initial one, illustrating the rise in susie's rage at lancer's betrayal
i absolutely adore that beat of silence before the guitars boom back to life 23 seconds in, as if susie is taking a breath before letting the anger really take her. it's like an aural version of how susie is lashing out at lancer
remember, the guitar is susie's bravado, her mask. right now, she's wearing her bully persona to its fullest, taken to emotion.
then 54 seconds in, the rest of the instrumentation comes in. just like 'susie's theme', the piano bass line returns, but it's been crunched with EQ, leading to it sounding distorted, pained, and haunting. it signifies the conflicting emotions within susie in this fight. it's not just rage that she feels, but sorrow and loneliness.
(there are also some crunched strings in 'vs susie', which is important for second sanctuary!)
the storytelling for this song is probably rather obvious, but it bears repeating that, again, the electric guitar is the bravado she puts on while the piano hints at who she is beneath, the hurt she carries.
the next song that's 100% related to susie is 'the second sanctuary':
it's her fountain, it's her song!
there are already analyses of this song, but that won't stop me from adding mine to the mix!!
remember what we said above about the guitar, piano, and strings?
second sanctuary is the synthesis of that, showing susie's growth as a character. in fact, i think comparing the way instruments are used in second sanctuary compared to susie's theme and vs susie is a way to understand just how far she truly has come
sweeping strings, puzzling guitar riffs, and a drum kit set the stage in the first half of the song. in contrast to the previous two songs, the guitar here is accompanied by strings that aren't crushed this time.
cornplating here, but i'd equate the presence of strings as susie's hope. it was crushed and almost nigh inaudible in 'vs susie', but through her growth, the strings come back as something majestic and present. it complements the guitar, which is still about her bravado, but in a way that feels 'fuller'.
this then leaves the piano, which i'd postulated was related to susie's loneliness, her inner self
at this point in the story, susie got to witness kris play the piano and something about their performance moved her so deeply, that it healed the trauma of that event for her. she becomes vulnerable when she tells kris the story, even confessing that had she known kris could play the piano earlier, she would've hated them for it. in other words, kris would've become part of that trauma
instead, they're the one who healed it and now she wishes she could play the piano too. through her friendship with kris, the piano transforms from something that represented her loneliness into something that signifies her friendship and trust in kris
this is why in 'the second sanctuary', the piano part (in my opinion) is emblematic of what kris means to susie.
there is a notable 'call and response' between the strings and the piano after 1:39, where the piano steps in and supports the strings. it's beautiful how the two play off each other, creating a dimension of sound that otherwise wouldn't exist in the song.
if we use what i said prior, this is equivalent to kris supporting susie's hopes (and thus susie herself). susie thinks of kris' support as something integral to her hope
(interestingly, toward the end of the song when the strings are gone, the piano plays the legend/dark sanctuary at a diminished volume alongside the choir)
so! tl;dr, the guitar (susie's bravado, her exterior self) is bolstered by the strings (her hope), which is then also supported and complemented by the piano (her loneliness turned into proof of her friendship and the presence kris has in her life)
i love toby's storytelling in his music and even if it might not be what he entirely intended, i feel it can illustrate susie's progress as a character very well!
of course, honorable mention goes out to rude buster/ruder buster. while i don't think it's exclusively susie's theme, i do want to point out that the piano takes the lead in rude buster while it just flat out has a solo in ruder buster
my read on this is that kris represents piano and the piano lead is due to kris being, well, the leader. ruder buster is a song concocted in kris's dark world, thus the more prominent piano segment in the lead
however, i could be persuaded to believe that it's because susie feels more comfortable in the fun gang, thus the piano's prominence! maybe...
sources below for the music:
the second sanctuary deconstructed
vs susie deconstructed
undertale sample spreadsheet