When I opened my email and found Natalie Bangheri's delightful artwork depicting Ela and Scythe from PROPHET, I was struck by the joy she'd added--Scythe's just-fed tranquility, and that secretive quirk of humor in Ela's quiet little smile and bright eyes. 
Humor--to say nothing of outright joy--was the furthest emotion from my mind when I wrote the initial scenes of PROPHET. After all, my brave young heroine, Ela, had just accepted a death sentence. How could she possibly enjoy life while facing assassins, battles, tyrant kings, and hideous venomous monsters at every turn?
However, mortals in every realm intuitively stave off stress by seeking joy in some form. A hug from a cherished sibling before facing an army, spiritual encouragement from prayers, coltish devotion from an overgrown monster-horse, and even jesting with fellow prisoners when you've been unfairly sentenced and tossed behind bars. With every chapter, the more I wrote of Ela's perils and fears, the more joy surfaced in the manuscript and in my characters' thoughts and emotions. 
Mid-manuscript, I paused, stared at my computer screen, and thought, "Even Shakespeare's tragedies featured clowns. Why shouldn't I add some joy and let readers have fun along the way?" 
What do you think? Do dark scenes demand a touch of joy now and then--the merest hint of hope to encourage our heroes, heroines, and readers on their journey?