What kind of story is Yoshi Legacy: Heroes of the Mushroom Continent?

Sure, it looks like a run-of-the-mill save-the-world scenario, but it's actually a story about the entirety of the Mario Universe. Parts of the story have to do with how figures in this game's history, such as Mario and Luigi, were set up, and how it affects the characters that are portrayed in the series.

Yoshi Legacy: Heroes of the Mushroom Continent is ridden with much sadness. Most of the characters have something dark hiding in the back of their minds; from a lost item to something that could be much larger and tragic. In the end, all of these characters' problems will become known and clear, and what they all are rooted in create the ending of not just my series, but the Mushroom Continent's history as well.

I haven't been developing this story for three years for no reason. It's come a long way, and it's still going. I love getting any kind of support or feedback for how I'm doing, so any comments are appreciated!