Taking the fact I've been listening to this song for quite a while, it might say there alone that it is a personal favorite.
But not just that, this song takes a lot into it. You feel the emotion that Samus Aran has been sort of led to have over the pass while, especially in Prime, and that is a feeling of loneliness. Rain, what a marvelous effect that rain had, and the entire song became the epitome of rain and it's effects on a temperament. Soothing, but you just begin to think when you listen to it. It just mezmerizes and sucks everything in.
The Wingless, I look forward to the rest of your works, especially if they keep up with this song. You did an incredible job.