The internationally bestselling butts-gone-bad are back! Tyrannosore-arse Rex versus Tricerabutt: Who kicked more butt? Stenchtiles and Farthropods: Which smelled most foul? Exstinktion: How did the buttosaurs get wiped? This book will tell you everything you need to know but were too grossed out to ask about prehistoric butt-related life forms and the complex stenchology of their environment. Never again will you look like a fool when somebody asks, "What buttosaur is that?" A must-have for every kid with a butt!