City of Glass

Clary heads to Idris for a cure for her mother. With Jace she finds the Book of the White at the Wayland manor and learns she was given angel blood before birth, while Jace got demon blood. Demons attack Alicante, and Sebastian kills Max Lightwood. Jocelyn wakes and reveals that Jace isn't Clary's brother: Sebastian is. Clary creates the Alliance rune, joining Shadowhunters and Downworlders, and marks Simon with the Mark of Cain. Valentine kills Jace to summon Raziel, but Clary writes her own name over his. The angel kills Valentine and brings Jace back to life.

1. ChangeJocelyn lives in the book

   In the book, Jocelyn wakes from her coma and survives. On the show she dies in S2, a change Cassandra Clare herself approved.

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2. ChangeMax makes it on the show

   In the book, Max Lightwood dies in the attack on Alicante. On the show, Sebastian hurts him, he falls into a coma and pulls through.

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3. ChangeWho kills Valentine

   In the book, Valentine summons Raziel at Lake Lyn, and the angel himself kills him. On the show, Clary is the one who kills Valentine.

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