I read this book and I forgot the name of it but all I remember is that there is a girl as the main character. She's on a ship with other people and the ship gets attacked by vulcren which are a flying horror creature. I also remember that there is a white stag and she needs the antler to turn it into a necklace to master her powers. She is able to use her powers for light.
Could it be Shadow and Bone by Leigh Bardugo? It's got monsters named volcra, ships, and an antler necklace.
Alina Starkov is a teenaged orphan, a citizen of the Kingdom of Ravka. She grew up with Malyen Oretsev at a orphanage in Keramzin, which is sponsored by a wealthy patron. As the story begins they are marching to the Unsea (also referred to as the Fold), a perpetually dark, barren, strip of land cutting most of Ravka off from the sea. Periodic expeditions are sent across to take goods to the sea and bring back imports. The crossing is dangerous because the Unsea is inhabited by monsters named volcra. Early in their crossing, the volcra attack, and, while saving Mal, Alina displays an extraordinary Grisha talent. The Grisha are people with the ability to manipulate the elements to use as weapons, e.g. to call fire, to summon wind, to stop hearts. Alina can summon light.