The way this is composed brings just one word to my mind: Epic. It is like sailing over the vast sea, scaling the great windswept Dragon Roost Mountain, and, as stated before, a prelude to a great siege. I could see this song playing as warriors dig into the ground of the island, prepared for the onslaught of darkness that had overcome Hyrule - no matter how terrible the odds or how dark the day. Yes...the forces of darkness approaching across the sea, prepared to claim the island and it's power...truly magnificent.
You've done outstanding work here; I thank you for all your hard work and encourage you to continue on in such a wonderful fashion.