Fallen Blade, book 6: Darkened Blade
Kelly McCullough2015

Aral Kingslayer has nothing to lose - and only justice to gain. Torn apart by the death of his goddess, he must avenge her in order to save himself from being lost forever....

It's been nine long years since the death of his patron, Namara, and exalted assassin Aral Kingslayer desperately misses the thrill and glory of being a higher power of justice. Now he is haunted by the ghosts of the past - and by the ghost of the lost goddess herself.

When Namara calls upon Aral in a dream to seek justice for her death and the ruination of her temple, Aral must obtain the help of his fellow former Blades and his Shade familiar, Triss, to pursue the vengeance he knows Namara deserves. Even if it means attacking Heaven's Son - and going against one of their own - in a bloody battle of epic proportions...