Hm...
A bit short and not much variety in it, BUT it makes for a perfect background, something that ambient songs are meant for.
It's not exactly scary, more like a cryptic, uknown thing, the title fits in here perfectly.
Unfortunately, like i wrote earlier, it's kinda short and doesn't exactly loop well, but on the other hand it creates a specific mysterious atmosphere, and it has some potential for expanding, and being a full fledged song, would be really nice if you'd work with it a bit.
I'm a bit torn apart as far as rating goes, it's relly well done but it's a bit short, though i really like it so i'll give you a 9, it would be a 10 if it looped better ( or was longer ).
Anyway, keep up the good work =)