Farewell, Horizontal!

The Cylinder — a giant structure rising miles above the surface of an unknown Earth of the future. Ekster rejected the boring nine-to-five job at the horizontal levels of the megacity to find himself at the very center of real events — on the "vertical," where freelancers, warring tribes, and other nomads live along cables and ramps on the outer edge of the building.
Ekster's dream is to become a successful graphic designer and create battle emblems for the warring tribes. And, like all citizens, the microchip in his brain is connected to a complex computer system that manages the economy.
But when Ekster takes on a really cool assignment — creating entirely new "icons of death" for one of the most powerful tribes, — he embarks on a dangerous journey that will lead him to the Dark Side of the Cylinder… and beyond.