Silent Hill much?
Man you need to work on the next Silent Hill game, because that made my guts churn. Really I've never heard anything like this on the portal before, how did you make it? Because it sounds like you really went to some abandoned, jail/slaugterhouse...on Mars, and just start recording.
The moans had that echo... that made you feel like something was all around you waiting to strike. And that slithering squishy sound just kept my suspense up the whole time...
In short, you sir have some real talent.