Ascendant by Diana Peterfreund

Forget everything you ever knew about unicorns. The fluffy, sparkly, friendly “horses” so popular the world over don’t exist. Real unicorns are killers. Don't miss book 2 in the thrilling Killer Unicorn series!

Beasts the size of elephants, with cloven hooves that shake the earth, hides impervious to bullets, and horns that contain a deadly poison, unicorns can outrun a sports car and smell a human from a mile away.

And they can only be killed by virgin warriors descended from Alexander the Great.

Astrid Llewelyn is now a fully trained unicorn hunter, but she can't solve all her problems with just a bow and arrow. Her boyfriend, Giovanni, has decided to leave Rome, the Cloisters is in dire financial straits, her best friend's powers are mysteriously disintegrating, and Astrid can't help but feel that school, home, and her hopes of becoming a scientist are impossible dreams.

So when she's given the opportunity to leave the Cloisters and put her skills to use as part of a scientific quest to discover the Remedy, Astrid leaps at the chance. Finally, she can have exactly what she wants—or can she?

At Gordian headquarters in the French countryside, Astrid begins to question everything she thought she believed: her love for Giovanni, her loyalty to the Cloisters, and—most of all—her duty as a hunter.

Should Astrid be saving the world from killer unicorns, or saving the unicorns from the world?