Ichor is the blood of angels and demons. Ichor is gold for angels and black, viscous, thinner than blood, and totally opaque for demons. Demon ichor is infused with demon energies, acidic, can burn the skin, and is somewhat toxic to humans if it gets into their blood through wounds or other means, though it can have varied effects when given in careful concentration.
Ichor in other beings
- Clary Fairchild was unwittingly given angel blood, particularly Ithuriel's, while in her mother's womb by Valentine, seemingly making her more special and giving her the ability to see and draw Marks not found in the Gray Book.
- Jace Herondale was also given Ithuriel's blood, also while in his mother's womb, as part of Valentine's experiments. It gave him innate strength and skill far superior than ordinary Nephilim. This excess angelic blood also Turned the vampire Simon Lewis into a Daylighter.
- Sebastian Morgenstern was also given doses of demon blood, specifically Lilith's, while in Jocelyn's womb. It gave him superior strength and agility when compared to most Nephilim. It also gave him the cruelty that comes with the demonic nature he was born with. The demon blood was burned out of him by heavenly fire; before he died, the persona that his blood made him take on was destroyed first, revealing the person he could have been without the blood.
- Valentine Morgenstern also injected himself with both Ithuriel and Lilith's blood. The ichor enabled Valentine to perform magic, with Jocelyn even going as far as saying that Valentine was as close as any human being can get to being a warlock. While it also provided him with some strength and agility, its effects on him were less in comparison to the effect it had on Jace and his children, all of whom received the blood before birth. The angel blood also gave him a sudden feeling and sense of euphoria.
- Jocelyn Fray was also given doses of demon and angel blood by Valentine. The angel blood gave Jocelyn the determination and focus to keep going and not commit suicide, as she had wanted to. She, like Clary, also received some ability to use runes unconventionally, though in a significantly less degree compared to Clary's; for example, she and Clary were both able to place—and later withdraw—three-dimensional objects within an otherwise flat surface or material, such as on drawings or paintings, but she does not have access to other runes that Clary has.
- The Endarkened were Shadowhunters infused with Lilith's demon blood by drinking it from the Infernal Cup. The demon blood twisted their allegiance from angelic to demonic and affected their general psyche.
The term "ichor" comes from the ancient Greek word for the blood of their gods.
- Individuals with ichor in their blood often happen to have golden eyes, as seen in James, Jace and Mark. However, this is not due to the ichor, per se, but rather because of the presence of magic in the individual's bloodline, with golden eyes being one of the many possible signs.
- The Shadowhunter's Codex
- City of Glass
- The Mortal Instruments (book series)
- Lady Midnight
- City of Bones
- City of Ashes
- City of Heavenly Fire
- City of Lost Souls
- "Golden eyes mean there is magic in that person’s bloodline," Cassandra Clare on Tumblr
- "The golden eyes say 'magic in your bloodline' not 'Herondale.'" Cassandra Clare on Tumblr