Out Past the Stars

Gunrunner empress Hail Bristol must navigate alien politics and deadly plots to prevent an interspecies war, in the explosive finale to the Farian War space opera trilogy.
When Hail finally confronts the Farian gods, she makes a stunning discovery. There are no gods—only the Hiervet, an alien race with devastating powers who once spread war throughout the galaxy long before humanity's ancestors crawled out of the sludge of Earth's oceans.
But this knowledge carries with it dire news: the Hiervet have returned, eager to take revenge on those of their kind who escaped. And they don't care who gets caught in the middle of the battle—Shen, Farian, or Indranan.
Once again, the fate of the galaxy is on the line and Hail will have to make one final gamble to leverage chaos into peace.