Rain World's music composers did an amazing job at supporting the various atmospheres players encounter.
Unmarked spoilers ahead!
- "Sundown", the rainy theme that plays in the main menu, encapsulates the desolate nature of the ecosystem that evolved throughout the game's abandoned architecture.
Survivor/Monk/Hunter Story Mode
- "Pictures of the Past" is a highly emotional piece that plays near the drop that separates the Survivor from its family, taking it and the Monk to unfamiliar outskirts.
Early Gamenote
- "Unseen Lands" fittingly introduces the unforeseen circumstances the lone Slugcat first shows up in.
- "Threat - Outskirts" accompanies the earliest dangers that players encounter, hyping them to adapt to such.
- "Proxima" plays in the Outskirts' path to and from the Farm Arrays, like an offbeat warning of the dangers the Hunter nears in the seemingly humble flats.
- "Industrial Attrium" marks the entry into the Industrial Complex, yet another unfamailiar location to explore.
- "Threat - Heavy Industrial" emphasizes the changes that result from the travels to a different, more difficult environment.
- "Mud Pits" is an airy tune that fits the aquatic Drainage System.
- "Digital Sundown" is a somber reprise of the game's main theme, accompanying visits to what remains of Looks to the Moon.
Midgamenote
- "Threat - Pipe Yard" is a light, chaotic track that adds to the varied architecture of Downpour's new Pipeyard region.
- "Fragments" is a melancholic song in Pipeyard, with bells near the end to convey the impact of the Ancients' absence.
- "Veiled Northstar" is a hectic theme that plays as Slugcat traverses the lengths of Pipeyard's Sump Tunnel, as well as Shoreline's entrance to it.
- "Black Moonlight"'s broad, wide noises introduce the lighter areas of the Shaded Citadel.
- "Floes" has a more ominous melody and strings, as the darkness of the central Shaded Citadel is traversed.
- "Random Gods" is an triumphant rehash of the main theme, building up to the impact of Slugcat's visit to Five Pebbles' puppet.
- "Threat - Chimney Canopy (Gutter)" is an alternative to Chimney Canopy's main threat theme, as earthly as the Gutter's mud flows.
Late Gamenote
- "Distance" is a soothing track that shows up amidst the vast Farm Arrays, as well as the exit from Outer Expanse to the Outskirts.
- "Emotion Thread" is a calm yet fittingly emotional prelude to the standard descent from the Farm Arrays.
- "Threat - Sky Islands" is ambience as ruthless as the Sky Islands' environment, keeping the player on their toes as danger lurks everywhere.
Arenas
- "Weyuon" carries the untamed tones of the story world's wilderness into the arenas — and cranks it up to 11.
- "Noisy"'s hectic electronic beats are great for Arena's drop-in scuffles.
- "Wandering Cut" is a lowly tune that fits more slow-paced Arena experiences, as well as an area in the Outer Expanse.
- "Wired" is a cheery, jungly theme that's quite uniquely lively compared to many other Arena tracks.
More Slugcats Campaigns
- "Threat - Waterfront Complex" is a jaunty remix of Shoreline's threat theme, played prior to the vast lake that Waterfront Facility became.
- "Lost City" is an epic reminder of the Artificer's unwaving will to get revenge on the Scavengers as they reside in Metropolis.
- "Threat - Metropolis (Day)" clashes and clangs through the Artificer's final conflicts, as she becomes more of the true threat; she is remembered less as a nuisance for the Scavengers to off, but more for her lust for their blood.
- "Garden" is an emotional theme that plays near Submerged Superstructure's Bitter Aerie. It fits the Expedition end screen just as well to boot.
- "Fragile" is an airy soundtrack that appears in the light of Bitter Aerie proper.
Saint Campaign
- "Chilblain Grace" drops the changes in Saint's time like a hammer, as the campaign opens with it desperate not to freeze in the Windswept Spires.
- "Sheer Ice Torrent" is a threatening replacement to "Bio-Engineering" within the Industrial Complex... or should we say Icy Monument.
- "Eyes of Iron" is a menacing track in the heights of the sterile Glacial Wasteland. It coincidentally fits the Saint's eventual attunement removing its need for technical pacifism.
- "They Say" introduces the lush Undergrowth that coiled itself through what was once the Drainage System.
- "Reclaiming Entropy"'s lone harp fits the Saint's will to stay in its changing world, and it perfectly marks the End of an Age for the Ancients' constructs.
Other
- "Train Tunnels" is a positively foreboding track that appears as the player configures their Expedition experience.
- The music for the Downpour slugcat showcase is extremely hectic and engaging, perfect for the action that reveals the new slugcats' abilities.