Wow! That sounds like a stupendous plot! I wish I came up with as good a plot for my first novel-length story. (Basically, it didn't have one, it was just characters and setting with nothing to do... sigh! That was five years ago, thankfully!) You have tons of imagination and great talent. Please don't give up, writing is hard work, and you can do it! Keep writing, and let us know how it goes with "Silent Hoofbeats"!
Unicorn writer of: "More than a Myth" Intro, Part I, Part II
