Mia And The Lightcasters by Janelle McCurdy
Twelve-year old Mia has always dreamed of being an umbra tamer. Like many other cities, Nubis has been plunged into Darkness by the shadowy Reaper King - a figure the children of Nubis only know in their nightmares, and through horrible rhymes warning them to stay safely inside the city walls.
When the Reaper King's minions capture her parents and take over the city, Mia, her friends and her little brother must travel across the Nightmare Plains to reach Stella, the City of Light. But getting there isn't going to be easy. Mia must learn to harness her umbra taming abilities if she stands any chance of confronting the king and rescuing her parents. If she can't, she'll lose her soul, and her family, to the Darkness forever . . .
The Umbra Tales: Mia and the Lightcasters is the first in a bold, cinematic, commercial new three book series, perfect for fans of Percy Jackson, Katie & Kevin Tsang and Abi Elphinstone.