It was tough to decide between AA, Layton and Xenoblade. But as AA isn't technically Nintendo, and as Xenoblade is the best thing ever, it had to be this:
There's something so very familiar about the Xenoblade soundtrack. It just fits so well. Be it the Gaur Plains theme during your first real "free" area or the Mechanical Rhythm for later game enemies, the OST adds to the game in every possible way.
So why did I choose this song? For some reason the story of Xenoblade really resonated with me and for all the best story sections, this song played. The first time is during "that scene" in Colony 9 during your fight with Metal Face and from there it just gets better and better. Whenever this song played you knew something was about to happen, that there would be some twist which would leave you an emotional wreck and the vision system made those cutscenes where you knew what would happen all the harder to watch. It's not the most popular song on the soundtrack, sure. But it's one I'll never forget and at the end of the day, is that not the point?
Essay Pro