I can't be certain, but the music for Castle V Castle sounds very much like it was made on an old Roland TR-808 drum machine or equivalent plug-in. Your ears will be familiar with the 808 even if your brain isn't - it's about as ubiquitous in hip hop as the Amen break. That's actually quite fitting, because this minimalist strategy game has the rhythms of a call-and-response rap battle. That's something you could say for all I-go-you-gos to an extent, but the bellicose back and forth here is especially sizzling, snappy, and scintillating.
(The game music is very different from the trailer music.)