This answer contains spoilers… (view spoiler)[I actually don't think it's that violent for adults, maybe for little kids. There is a lot of shooting going on especially with the main characters the author loves to do. It's brutal in my opinion. While Harry Potter definitely is more violent with the killings, I honestly think that Flame of Olympus is worse. Just using guns on the main characters, a lot of torture scenes from the CIA, some of the CIA agents wanted to attack children while the Olympian Gods were at a grocery store and they had to beg the agents to let the kids go free and let everyone else go free. It's just be cautious. :) My humble opinion. (hide spoiler)]
Catherine It's got Roman gods, it's not very violent, and it's nowhere near as good as Percy Jackson.
Grace This is as good as Percy Jackson and I am a huge FAN of Percy Jackson. It is violent but not super violent. More violent then Percy Jackson I think. An AMAZING BOOK!!!!!!!!!!!!!!!!!!! Just Roman gods by the way!
Hayden Dollinar No this book is nothing like percy jackson it just more adventurous then Percy Jackson. This book just have roman gods nothing more nothing less. This book is good but bad. Yes, It is violent!
AnimalLover It does involve Greek/Roman gods, I love it, some violence and would recommend 11+! Great book, I have the series myself and hope that others will too...
Claire It does not invole Demi-gods but other than that it's pretty close to it. It just involves Roman gods. It is a very good book. I highly recommend it! It's not very violent and by that I mean it mentions cuts and bruises and a little bit of fighting. Warning: At least two people die and some creatures die too.