Master of Chaos, from the Fighting Fantasy game book series, written by Keith Martin, illustrated by David Gallagher, and cover by Les Edwards.
“The staff of rulership must be regained!
You have no choice but to take on this mission. The Master of Chaos - warped by centuries of evil - holds a Staff of Power. From his lair in the ruined city of Kabesh, he plans to unite the forces of evil and chaos and plunge Titan into a Dark Age. YOU must find him and win back the Staff ... whatever it takes.
Part story, part game, this is a book in which YOU become the hero! Two dice, a pencil and an eraser are all you need. YOU decide which routes to take, which dangers to risk and which foes to fight!”
There are a few rule unique to this book, such as a notoriety score, which represents how much attention is being paid to the player, the choice of three "Special Skills" from the following list: Acute Hearing, Animal Wisdom, Blindsight, Climbing, Move Silently, and Tracking, and a lower skill score due to lack of weapons at the outset