Jace, Abi, Clem and Eric are back in school for their 4th year and they are facing their biggest challenge yet. They are all four trying their hardest to advance to their next level so that they will be able to confront better the challenges before them, but none of them are managing to do so yet. Jace received a map from a secret benefactor which they needed to follow to get to the Umbral Forge, in order to re-write the Grand design. Jace was chosen by the Empyrean Flame to create a new flame and he was adamant on seeing this quest through to its end even if it killed him. He had seen the gnawing monsters which were eating the Grand Design and he worried that time was running out. Our group of four young heroes travel to distant places namely Siberia and the Gobi Desert to undo a millenia of damage done to the world by a bunch of power-hungry soothsayers. They also do this with the heretics on their heels all the way, and this is what pains Jace the most, the fact that it is his mother who is out there trying to kill him. She had become a zealot and had taken the machina into her own body so Jace knew that if she challenged him he would not think twice to kill her. They had to locate the heart of eternity and the 4 orichalcum keys, confronting skeletons and Meriwa herself as well as Mother Weaver in all her glory but he had the backing of the dragons of Shambala behind him even though his own clan ended up betraying him. I love the loyalty of our four friends who always look out for one another and who persevere at the cost to their own lives. This is one of the best series of wuxia adventure, full of cultivation mastery and so many twists and turns to the story that I have read so far, and this, book 4 managed to keep me hooked till the very end. I look forward to reading book 5 in this riveting series.