"21st Century Schizoid Man" lives up to its title, with its screaming guitars and saxes and apocalyptic lyrics:
Blood rack, barbed wire
Politicians' funeral pyre
Innocents raped with napalm fire
The second half of the "Lizard" suite, starting out as a quiet ballad that slowly grows increasingly ominous and Gordon Haskell sounding increasingly pissed as the section comes to a close, which then explodes into a suffocating cacophony of horns, keyboards and guitar. And it all closes with a creepy funeral march with Fripp's weeping guitar....followed by the sounds of a carnival spiraling out of control.
Most, if not the entirety of Red. The intro to "Starless" alone can suck the warmth out of any room with its Mellotron intro and creepy lyrics which seems to be about someone crossing the Despair Event Horizon, and even though the listener is taken to the heavens at the end of the song, the same intro is played one more time, only with a sharper, more menacing edge. Then there's "Providence", which is one of the most unnerving pieces of music ever to grace human ears. The first half alone will have you looking around the room, convinced that something is staring at you. It's fucking terrifying. Finally, the ominous "Red" itself, particularly in the middle section with the creepy cello, and the distorted guitar and bass which sets the tone for the entire album.
The song "Indiscipline", from Discipline, is a very heavy song with quiet parts and with a spoken word part by Adrian Belew. The original recording is not too impressive, but live versions extend it out to 8 or 9 minutes, lengthen the quiet parts to absurdly tension-building levels, and have Belew's narration take on a psychotic quality, until the song crashes into the noisy section. The full effect is terrifying.
From Three of a Perfect Pair, we have Side 2 opener "Industry". It's the quiet parts of "Indiscipline" with the heavy bits removed, the lyrics removed, machine noises added, and the tension taken to an absurd level where the entire song constantly sounds like it's about to collapse on itself. This goes on for seven minutes straight.
"The Devil's Triangle", which starts off as a modest variation of Holst's "Mars, the Bringer of War" before turning into pure disregard for peace treaty by the end. And just to be a little more unsettling, an excerpt from "The Court of the Crimson King" swoons in and out in the final minute...