The Void Dragons by Scott Reintgen

Lunar and the Dread Knights must defeat a deadly new enemy to save their solar system in this third book in the New York Times bestselling sci-fi and fantasy mash-up The Dragonships series, sure to delight fans of Skandar and Eragon!

Before disappearing, Proteus predicted a threat was approaching the solar system. Something big. But when a year goes by with no attack, Lunar Jones is forced to focus on the here and now. Phobos and Deimos both need new riders. More recruits than ever are trying out for their now-famous crews. And Lunar and Dread are busy preparing for the Solar Summit—a meeting between the planetary dragons that happens once every 500 years.

Lunar is so preoccupied, he almost flies right by the first warning: a derelict ship between Earth and Mars with its crew missing. When Lunar stops to investigate, the evidence points to an attack by nine creatures that afterward took flight with one aimed at each of the nine planets. It doesn’t take long before the entire solar system is locked in battle with creatures called void dragons, an undead enemy that proves very difficult to destroy.

Worse, their arrival signals the approach of something that would make the shine of even the brightest stars tremble: a black hole. If Lunar and the Dread Knights want to save their world a third time, they’ll have to forge new alliances, summon new powers, and be willing to sacrifice everything.