Terran
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This might not come as a surprise to some of you, this song has a very industrial feel to it. It is the perfect song for a mech player, I can only imagine a huge Tank, Thor and Hellion army moving through the center of Shakuras Plateau while SCVs build more factories in the main base, the sound of terran machinery working in the background preparing the next round of reinforcements.
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Hard work is being put in there to give you all those beloved tanks.
Protoss
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I somehow imagine the Protoss base as a huge rave, the Chronoboost, the Pylons turning in perfect sync, Warpgates, Robo Facilities, all those lights and lasers, it just goes so well with the music. I wouldn't surprise me if this was the music Zealots danced to on their free time.
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Shiny!
Zerg
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This one was a little harder, I would say that Neurofunk DnB makes me think of The Swarm the most, all those weird sounds and the Chaos, it just puts you in a tense state. I can imagine endless waves of units overwhelming a underprepared Terran opponent, mutas flying in killing your workers, whole base on fire, marines being chopped to peices by Ultralisks and many other gruesome things that the Swarm is capable of.
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So that would be it, if you have any other music that makes you think of any of these feel free to share it here!
EDIT: Fixed some spelling mistakes. Also sorry for the terrible writing and such, I'm trying to improve my English writing skills, if you see any little mistake feel free to point it out aswell.