Rise of the Supernatural Heroes (Mystical Warriors book 1)

From stories of ghosts and spirits of the dead comes a new kind of story unlike as never been told before: ghosts with skin that can harness the power of Elemental Powers: Fire, Ice, Earth, Water, Dust, and Air.

Join Matthew and his friends as they get entangled in a world they'd never thought come to be. A world where supernatural meets mythology and the modern world. Meeting with old ghostly warriors with wings, the group of kids must undergo training as they must battle an evil being living the planet's core.

But there are also dangers luring on the planet's surface as well, and seek to destroy the last remaining defenders seeking to keep the evil in the core from escaping. And the simplest thing to bring back the evil being: destroy a cybernetic arm of a person's right arm that makes an invisible ghost to have skin cells.