10 Things You Didn't Know About Portal
5. Portal 2's Soundtrack Changes As You Play
If you're a fan of bleeps, bloops, and assorted synthesisers that combine to sound like a malfunctioning printer, the Portal 2 soundtrack is for you! Jokes aside, both Portal games have fantastically atmospheric musical scores which complement their respective games perfectly. Portal 2's soundtrack takes things to the next level, however, by actually changing as you play.
The test chambers in Portal 2 are accompanied by what's called "dynamic music", which reacts to how you play and evolves as you solve the puzzle. Each test element makes a unique musical sound, adding new layers to each track when activated or used.
For example, directing a laser into a receiver to open a door activates a layer of minimalist synth, and bouncing on Repulsion Gel adds a series of bouncy arpeggios to the soundscape.
This procedurally generated soundtrack is an ingenious concept implemented flawlessly, and it's a great way of not only giving the player an aural indication of their progress, but also a neat way of making the Aperture facility feel truly alive.