From the campaign:
The Book of Exalted Darkness is two things: a holy decopunk campaign setting (think Rocketeer or Sky Captain and the World of Tomorrow) and a sourcebook for playing evil characters in D&D 5E.
Together they make for a slick and stylish campaign setting with a bevy of meritorious NPCs paired alongside a grimoire of vile and forbidden evil, the PCs gaining a little more edge through their trickery or perversion of the very technology that makes the world so unjust.
Choose your adventurer's Inherent Heresy, devise how best to destroy the 9 spheres of the Celestial Heroes, and embody the very essence of wickedness as you strike at the heart of the world's immortal rulers greatest works, taking all of they've built as your own or tumbling it all to destruction!
The campaign's about 3/5 of the way to its goal with still 12 days left on the clock.