Shadow and Bone by Leigh Bardugo

I've only gone halfway so far, but it's already interesting.  Shadow and Bone stars main character Alina Starkov, an orphan plucked from a distant village after war and put in the duke's orphanage-turned-household.  The Grisha, people with powers, are to be trained in the King's army and at age 8, Alina is to be tested.  After proving herself to be not-Grisha, years later she leaves the orphanage to work in the second army under the power of the darkling.  And so far, the villain is the Fold.  Also called the Unsea, a black shadow filled with monstrous creatures that slashes through the true sea separating the country of Ravka.  Until a day where Alina and her fellow cartographers set out on a mission to pass the Fold into west Ravka for trade.  Long story short, they get attacked by bat-like creatures (bats but much bigger), and most of the people on the ship got killed, except Alina and her childhood friend Mal, who barely escaped.