It's good, but it sounds almost exactly like the story between Legend of Zelda Ocarina of time and Wind waker.
I'm also writing a novel called "Elementals."
In a nutshell, here's the basic plot of the book:
In a series of unusual happenings, teenagers Tyler, Zeke, Blake, and Gary find out they are part of a select group, each granted with control over one of the ten elements. They quickly take this power for granted, except for Tyler, who feels a certain uneasiness even having the power. His uneasiness turns out to be quite reasonable when the elemental of darkness, a vile boy named Aaron, puts into action a murderous plot to claim total control over reality. The four friends make an attempt to protect the other elementals, but they will suffer enough difficulty protecting themselves.