Enemy of Shadow (Earth, Blood and Shadow Book 2)

The vengeful elemental god, Earth Darkness, has been reborn. Chasing after him, Phantist and Despanya follow the trail to the northern city of Ardent, where a plague of giant insects and the deadly servants of a mad bishop have created a living hell.
But, within the city, two of the last surviving shadewrights are hiding from the chaos... Two masters of the shadow-art whose aid is desperately needed if this war is ever to be won.
And, in a cavern under the city, Phantist's most hated enemy waits for him to settle an old score...