In other projects Wikimedia Commons. Through Clary, they found out that Sebastian intended to create an army of Dark Shadowhunters using the Infernal Cup —a demonic version of the Mortal Cup —with Lilith's blood, whom he was about to resurrect. However, she refuses him, because she believes that she is going to die She has been having visions of her lying dead, and Jace is crying over her dead body. City of Glass: Alec told Magnus that he felt trivial to him, that he would one day, after he dies or leaves, just become one of his many past lovers and Magnus would easily find another, which Magnus denied.
Jocelyn did not want her and Clary involved and was about to leave when Simon revealed to all of them that Clary had gone with Jace and Sebastian as part of her plan to find out their goal, and to communicate with them through the faerie rings she and Simon were wearing.
He dyes his hair black in City of Glass while he is impersonating Sebastian Verlac. In City of GlassMax is murdered by Sebastian, who strikes him with his hammer. It is said that Jace is seventeen years old, though that was assuming he was Valentine or Michael Wayland's son, and his real age is between a few years younger than Jonathan Christopher and a year or so older than Clary. She admitted to him that she was under Lilith's orders to kill the former Circle members, and that it had been her cult that broke her out of the Institute's Sanctuary.
When he came to get Isabelle from their house—the Inquisitor's house—he accidentally walked in on Isabelle and Simon role-playing in his room.