What is "bloodbones"

Bloodbones is a single-player roleplaying gamebook written by Jonathan Green and illustrated by Tony Hough. It forms part of Steve Jackson and Ian Livingstone's Fighting Fantasy series. The book was notorious for being the "lost" Fighting Fantasy gamebook, written during the books' original run but not published until 2006. It would have been 60th in the series in the original Puffin series had it been published at the time, and is 26th in the modern Wizard series.