This was nicely done because it set up a really creepy tone. The image that I envisioned in my head was one of going down a dark corridor. The only thing wrong is that there is not much variation. Still, it doesn't need a lot going on because it's fairly effective in its repitetion. In fact, it's really towards the beginning that you enjoy it the most as the tune seems the freshest. While not intentional, I like the images created on the song.
I keep seeing the one that looks like a big eye stretching out. That seems good for a horror icon. About 2 and a half minutes is when it gets the creepiest and it's the closest the song comes to making a transition. There's really more silence to accompany it further which is often effective. It could be used for a haunted house video game.