The Bones of Makaidos

As The Bones of Makaidos begins, a wall of fire protects the inexperienced villagers of Second Eden from a planned invasion of dragons and Nephilim, but how long will the flames last? Billy, Walter, Ashley, Elam, and the faithful dragons help the people prepare, but they are woefully outnumbered and will have to go back to Earth and recruit the humans who have the ability to revert to their former dragon state. In search of aid, Billy escorts Acacia, an Oracle of Fire, through a dangerous volcano portal.