Thanks, fixed the link!

The themes from the VGASPEC levels...I'm not actually sure if they were taken from other games. They sound like remixes of the originals.
I love the drum beats of the
Beast theme, they sound dark and give that feeling that you are in a prehistoric time period.
Beast II's sound gloomy and fits levels that have a dark, sad setting. Both themes can be even used in haunted levels like the Horror tilesets or some of the ghost-themed levels like in Holiday GigaLems.
Menace, I'm not too much of a fan of. It seems to fit levels that have small time limits.