The Shadowhunter's Codex

The Shadowhunter's Codex

The Shadowhunter's Codex

The Shadowhunter's Codex

Hardcover(27th ed.)

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Delve into the details of all things Shadowhunter with this illustrated guide to the knowledge and lore of the Shadowhunter world.

Since the thirteenth century, the Shadowhunter’s Codex has been the one and only manual for Shadowhunters looking to brush up on their demon languages, learn proper stele use, and discover just what exactly a pyxis is. Featured in both The Mortal Instruments and The Infernal Devices, this guide is a necessity for any young Nephilim on their journey to becoming a Shadowhunter. Beautifully illustrated, the Codex contains images of the famous Shadowhunter homeland of Idris, as well as depictions of demons and other Downworlders.

But this isn’t just any copy of The Shadowhunter’s Codex. It’s Clary’s copy, and as an artist herself, she’s sketched pictures of her friends and family in the book, and scrawled helpful advice in the margins. Of course, she couldn’t exactly stop Jace or Simon from adding their thoughts either. Part encyclopedia, part history, part training manual—complete with commentary from Shadowhunters who have seen it all—this beautiful guide is a perfect supplement to the #1 New York Times bestselling series.

Product Details

ISBN-13: 9781442416925
Publisher: Margaret K. McElderry Books
Publication date: 10/29/2013
Edition description: 27th ed.
Pages: 288
Sales rank: 61,186
Product dimensions: 6.30(w) x 9.10(h) x 1.20(d)
Age Range: 14 - 17 Years

About the Author

About The Author
Cassandra Clare is the author of the #1 New York Times, USA TODAY, Wall Street Journal, and Publishers Weekly bestselling Shadowhunter Chronicles. She is also the coauthor of the bestselling fantasy series Magisterium with Holly Black. The Shadowhunter Chronicles have been adapted as both a major motion picture and a television series. Her books have more than fifty million copies in print worldwide and have been translated into more than thirty-five languages. Cassandra lives in western Massachusetts with her husband and three fearsome cats. Visit her at Learn more about the world of the Shadowhunters at

A Simon & Schuster author.

Joshua Lewis lives in western Massachusetts with his wife, Cassandra Clare; three cats; and several thousand books. When not exhaustively researching arcane bits of the Shadowhunter universe, he can be found playing music, writing his own fiction, and keeping the weight of several thousand books from collapsing the house.

Read an Excerpt

Shadowhunter’s Codex
Shadowhunters do not use firearms, and typically we fight in close quarters. We also usually fight in short, improvised confrontations rather than in planned battles. As such, the basic armaments of the Shadowhunters are those hand-to-hand weapons that humans have used for thousands of years. Each of these come in endless variations, and you will need to tune your training to the specifics of your locale. Here we endeavor to lay out the categories of weapons and briefly discuss their pros and cons.

You should plan to quickly achieve a basic competence in each of these categories. Remember that demons are infinite in type and variety; a Shadowhunter never knows when she might face a foe against whom her preferred weapons are totally useless. You should, however, also give thought to what kind of weapon you might choose to specialize in. Some feel called to the longsword, while others will have a natural gift with a bow and arrow. Finding the intersection of your interest and your talent is a major goal of your early training.

Any decently stocked Institute should have on hand a selection of all of the weapons mentioned here, in addition to other basic useful combat tools such as: binding wire of silver, gold, and/or electrum; wooden stakes in oak and ash; amulets of protection; assorted holy symbols for major world religions; and basic magic implements (chalk, iron filings, small vial of animal blood, etc.). A truly well-stocked large Institute might add to that list such specialty items as lead swords, holy trumpets, bone staves, etc., depending on location.

Did you know?

Shadowhunter weapons are Marked with runes. While only seraph blades can cause permanent harm to demons, angelic Marks on other weapons will at least slow a demon’s recovery from a wound. Without these Marks, demons easily shrug off the effects of our physical weapons.


Swords are long hilted blades used to wound both by piercing and by slashing. Variants range from light and flexible blades wielded in one hand, such as the rapier, to heavy blades such as the Scottish claymore that require two hands to wield and whose blades may well be taller than a person. And more or less all possible stages in between are represented. Generally Shadowhunters have a preference for speed and agility in fighting, and so most who prefer swords specialize in one of the smaller one-handed versions. There are, of course, exceptions. Note that if you have never wielded a sword before, you may be surprised by how quickly your arm will grow tired, even when using a light blade. If you have never used a sword before, you can get an early start on training by practicing simply holding a sword out in front of your body, parallel to the ground, for a length of time. You will be ready to start actual combat training when you can keep the sword steady for thirty minutes.


These smaller blades are less tiring to hold, and frequently two are wielded at the same time. The trade-off is, of course, that they have a shorter reach than a sword, requiring you to be closer to your foe. They are also far easier to conceal than a sword. Seraph blades are typically wielded using techniques associated with dagger fighting, so you will want to grow proficient with these weapons no matter what. Thank you, Codex, because I didn’t know what a knife was.

You may also learn to throw knives and daggers, but it’s a very difficult skill to pick up, and daggers are usually more difficult and expensive to create than arrows, considering that you may lose them after a single use. Still, many Shadowhunters favor the throwing skill for its showy nature.

Haha Jace Throws Knives because of his showy nature.

We were all 14 once. You’d have learned it too if you could have.

Touche’, whatever your last name is.


Those who do not seek subtlety in their combat may wish to consider specializing in a weapon in these categories, whereby the enemy is simply bludgeoned with a heavy block of metal, possibly sharpened. You will come across few creatures that cannot be successfully defeated by the application of sufficient blunt trauma. The main advantage of these weapons is that, while one can learn finesse in wielding them, they tend to be effective even when that finesse is lacking. All the wielder requires is brute strength and room to swing. oh please please please Clary.

Tiny girl with a gigantic hammer! so anime!

In real life tiny girl with gigantic hammer has gigantic forearms.

The main disadvantages of these weapons are that, for one, they can be difficult to conceal, and for another, they depend on the enemy’s skin being less strong than the material of the weapon, which is usually true of Downworlders but may often be untrue of demons.

Flails and morning-stars, in which the aforementioned heavy chunk of metal is attached to the handle by a chain and thus can be swung around to build up more momentum, add more force to your blows in exchange for a higher risk of accidentally walloping yourself or the person standing next to you.


There are almost as many variations on these as there have been human armies in history, but they all have the same basic structure: a sharp blade at the end of a long sturdy stick. Traditionally these have been used in mundane warfare to give a fighter a longer reach than normal—which can be useful when fighting a foe on horseback (or giant lizard-back, in the case of some demons), a demon covered in tentacles, a demon with obscenely long arms, and so on. Today, however, fighting from horseback is obsolescent, and the annoyance of carrying a sharp six-foot-long pole around is rarely worth the trouble. You are most likely to see these carried by Shadowhunter guards as ceremonial weapons; you are also likely to find that these guards have other weapons on their person that they would wield instead in case of action.


These are the definitive Shadowhunter weapons for long-range fighting. They are lightweight and easy to carry, and you can bring a large number of arrows with you with little trouble. Often Shadowhunters will carry arrows with several different arrowhead materials, useful for fighting different kinds of creatures. (We recommended color-coding the feathers for ease in identification.)

Like sword fighting, archery is a complex and difficult skill, and you will need to train diligently to be able to use it in a real-life scenario. Shadowhunters almost never fire arrows from an entrenched stable position, like someone defending a castle from a siege. Expect to have to arm, aim, and fire your bow while in the middle of total chaos. Do not expect your archery instructor to let you take a bow with you into combat until you have demonstrated some serious skill.


The Nephilim are trained in the use of weapons, and our weapons are a vital part of our combat methods. It is important to always remember, however, that a Shadowhunter without fighting weapons is not helpless. The fight against demons is a desperate one, and weapons can be improvised from the environment—a tree branch, an andiron, a handful of pebbles thrown in the face of a foe. Then too the Shadowhunter should always remember that her own body is a weapon. She has been trained to be faster and stronger than mundanes, and in the panic of battle should remember her strength and make use of it. A weapon does not win a battle; the Nephilim wielding the weapon does.


There are, of course, as many nonstandard and exotic weapons as there are human cultures, and you may find that your local Nephilim have some combat specialties outside the common weapon types. These may include whips, sword canes, obscure weapons of martial arts traditions, household objects modified to double as blades, and so on. These rarer “specialty” weapons are not forbidden or discouraged from use. Indeed, a Shadowhunter is likely to be more effective with a weapon toward which they feel an affinity than with one forced into their hand by the dictates of training protocols.

Two specific exotic weapons are worthy of note here, one angelic, one demonic.

The aegis is a dagger that has been seethed and tempered in angel blood. They are incredibly rare, as one would imagine, since angel blood is not easily come by. There are only a small number of these in the hands of the Shadowhunters, and they are kept by the Iron Sisters and are not permitted to reside in an Institute. They are available for requisition in the armory, but the requestor should be prepared with a very good reason for the request. The Iron Sisters are not usually pleased to give them out.

The athame is a ceremonial, double-edged dagger, usually with a black handle and carved with demonic runes. It is used in demon-summoning rituals to draw blood or carve lines of magical force and is only for ritual use. The weapon loses its power if used in combat. It is one of the four elemental tools of the neo-pagan mundane religion Wicca; as such there are many false athame floating around. Warlocks can of course tell the difference on sight, but mundanes cannot. This can sometimes lead a mundane to accidentally possess a genuine athame, which is a great danger.


There is a legend told of the first seraph blade, which may or may not be true. The legend dates to the earliest days of the Iron Sisters, when they were few in number and the Adamant Citadel was merely a single adamas forge and a set of protective wards. In those days the paths from the mundane world to the volcanic plains of the Citadel were not as hidden and guarded as they are now, and it is said that a demon, a Dragon—for in those days Dragon demons were not almost extinct—found its way to the location of the Citadel. There was only a single Sister there working at the forge, and she was caught unawares and unarmed, having placed her faith in the impossibility of the Sisters’ forge being found by the enemy.

Laughing and threatening, the Dragon stepped through lava beds as though skipping across shallow streams. In terror, the Sister cast about her for a weapon, but all she had to hand were irregular jags of adamas, recently extracted from ore and waiting to be worked. She seized one and held it between her and the approaching Dragon like a pikeman preparing to receive a charge. Her hand trembled; she was afraid not for her own life but for the continued existence of the Iron Sisters: If the demons could travel here, surely they would overrun the Citadel soon enough.

Panic-stricken, she called out prayers to the forces of good. As the Dragon was upon her, she loudly abjured it in the name of Michael, the slayer of Sammael, general of the armies of Heaven. Promptly the adamas jag lit up, blue and brilliant with heavenly fire. The Sister’s hand burned where she clutched it, but with all her strength she thrust her makeshift lance and pierced the Dragon in the soft flesh under his jaw. She expected it to wound the Dragon and nothing more—but perhaps it would buy her enough time to flee.

Instead the adamas spear bored through the neck of the Dragon as if through paper, and around the spear burst flames of seraphic fire. The Dragon screamed and burned, and as the Sister watched, the demon staggered away from her, damaged in a way she had never seen a demon damaged before. Across the lava moat surrounding the Adamant Forge, the Dragon was overcome, fell to the ground, and burned for an hour.

The Sister fell to her knees in exhaustion and watched the Dragon’s carcass slowly fade from the world. She could then have rested—no one would have blamed her—but she was an Iron Sister, and by the time her fellow Sisters found her a few hours later, she had deduced the nature of the power she had uncovered and had drawn up on vellum the first blueprints for the seraph blade.

Iron Sisters: surprisingly badass.

Today seraph blades, or angel blades, are the fundamental weapon in Shadowhunter combat. They are as clear as glass, usually double-edged, and normally about two feet in length. Being adamas, they are incredibly finely honed and are capable of holding their edge indefinitely. They are thus potent weapons against any foe. Their true power, however, is revealed when they are named—when a Shadowhunter holds them and invokes the name of an angel. The spirit of that angel is said to then inhabit the blade for a time, and the weapon will glow brightly with heavenly fire, like the flaming sword of the angel who guards the Garden of Eden.

This heavenly fire is very potent against demons. Most demons can heal themselves from mundane injuries in our world fairly quickly, just as werewolves and vampires can. We Mark our mundane weapons (see sections below) to make them more potent, but even so, the best we can do with them is damage demons enough that they must retreat to lick their wounds, as it were. Only the seraph blade can permanently damage a demon, so that it must withdraw for more significant and lengthy healing or must return to the Void to repair itself.

After a time the power of an activated seraph blade will be exhausted, and it will need to be refreshed by the Iron Sisters in order to be used again. Depleted seraph blades can be brought to the weapons room of your local Institute for regular recycling.

Iron Sisters also badass at recycling!

Note that the seraph blade is a viable but drastically overpowered weapon in a fight against a mundane. Downworlders are harmed by them in much the same manner as demons, but mundane flesh pierced by a seraph blade will burst into flame and may consume the mundane entirely. The Clave has officially deemed this “awesome.”

Shadowhunters will not be so burned by seraph blades, given our angelic blood, but even so, activated blades can severely burn the wielder’s hands, and you should not touch a seraph blade until you have been Marked with the rune of Angelic Power. (Typically this is placed either at the base of the throat or on the inside of each wrist.) A Shadowhunter who has been stabbed by a seraph blade will not burst into flames, but it should be remembered that seraph blades are still blades and can kill a Shadowhunter by more terrestrial means, like any other sword or dagger.

By the way, most Shadowhunters think we have to name seraph blades just because Jonathan Shadowhunter thought it was important to make everyone memorize a lot of angel names. That guy was hard-core.

It does mean you rule at Angel Trivial Pursuit.

Also Angel Scrabble.

You’ll find weapons made of all kinds of materials in your local Institute, chosen for their magical properties.


Adamas is the heavenly metal granted to the Shadowhunters for our use by the Angel Raziel. The metal is silver-white and translucent, and glows slightly (although this glow may not be visible in broad daylight). It generally feels smooth to the touch, like glass but notably warmer and heavier. It is the hardest substance the Nephilim know of, and cannot be worked by mundane means. The Iron Sisters use seraphic Marks unknown to non-Sisters to shape the metal; to craft weapons and steles from it, the Sisters use forges that take their fire from the heart of a volcano.


This element is toxic to faeries. You will often encounter the term “cold iron” in reference to the fey; this is just regular iron. The term “cold iron” refers to the fact that it is cold to the touch, which was at one time believed to be associated with its magical properties. Iron takes enchantment and blessing very well. It’s generally believed that it is the large quantity of iron in human blood that causes its affinity for enchantment. It is especially worth mentioning that meteoric iron, the nickel-iron alloy that makes up many meteors, is a particularly good conductor of magical energy.


This type of iron alloy is usually not toxic to faeries. It is the purity of iron that grants its power over the fey. Steel does, however, hold a sharpened edge very well, and thus the Shadowhunter will normally spend a large amount of time training with steel weaponry to learn how to put one of those sharpened edges through a demon.


Silver is a metal with which all Nephilim are intimately familiar. Using a weapon made of silver is one of the only ways to permanently injure a werewolf, who will heal from a wound made by any other material. The element is toxic to vampires and causes them to experience pain, headaches, nausea, and so on, though it will not kill them. Silver is a potent conductor of magical energies, behind only gold and adamas, and as a result the fey also use a large amount of it in both their arms and armor, and also in their decorative arts. Shadowhunters have the unenviable task of learning to wield both steel and silver weapons, which differ noticeably in weight, and the Shadowhunter must in fact learn to switch between them quickly.


This metal is poisonous to demons. It is also an excellent conductor of magical energies, although it is rarely used to make weapons or tools, since in its pure form it is one of the most soft and pliant metals. Interestingly, it has both strongly positive and strongly negative associations in religious ritual. On the one hand its rarity, resistance to corrosion, and beauty has caused it to be used to symbolize high esteem, power, and the light of Heaven. On the other hand its expense and rarity has made it a symbol of greed and of the profanity of material wealth, as opposed to the sacredness of spiritual wealth. Thus, one will find gold used in sacred and powerful religious decorations and also in some of the darkest of demonic rituals.


Electrum is an alloy of gold and silver that can be found naturally in the earth. It has been known and used since the time of the pharaohs of ancient Egypt. Its lack of purity means that it is rarely used in specific rituals, but it is considered a good conductor of magic. It combines the mystical abilities of both silver and gold, in lesser strength than either pure metal but at significantly less expense than pure gold and without some of the disadvantages.


This element is used mostly as an intensifier for other materials. It is thought to help bring the abilities of other metals into better alignment with the wielder, and thus is often used decoratively, or to form hilts or handles of silver weapons, for instance.


Demon-metal is a noble metal (that is, one resistant to corrosion) that is believed to originate in the Void, and cannot be found naturally in our universe. It is black in appearance but is believed to be transparent and glowing with black demonic power. It is something like the demonic equivalent of adamas in that it creates wounds that cannot be easily healed by seraphic Marks and require much more involved medical attention. You will find it sometimes used to forge weapons or armor wielded or worn by demons themselves. It is incredibly rare to find it in the hands of Downworlders or humans.


The European rowan tree has long been known to have magically protective properties. It has been used in Europe to ward off malevolent spirits and enchantments for thousands of years. These properties, along with the tree’s density and strength, have made it a common choice for the staves of druids and other priests, and it is commonly used in the construction of Institutes and for arrows wielded by Nephilim.


The wood of Yggdrasil, the world-tree of Norse mythology, is believed to be the source of the so-called Mead of Poetry, the mythological beverage that would magically transform the drinker into a scholar. It has properties similar to that of rowan but is notably easier to work. It is also often used in a similar way to iron—it is believed to have a similar affinity with humans. (Norse mythology also cites it as the wood from which the first human was created.)


The oak tree is often considered the “most mundane” of woods, and from this very fact it draws its power. It has great strength and hardness and is therefore frequently the material of choice for wooden weapons. Stakes for vampire slaying, for instance, are traditionally crafted out of oak, which is believed to help guide the wielder’s hand to the source of demonic magic, in order to eliminate it.

Jace is considered the most awesome material to make a Shadowhunter out of.

I am both grossed out and confused.


You probably already know of holy water. In fact the use of water as a weapon against evil is well-explored in myths and legends. Water is the substance that, more than any other, defines and sustains life in our world. It can be made, with the application of ritual, to take into itself something of the angelic, to become not merely the water of life but holy water. Holy water has proved to be a useful weapon against demonic powers: It is severely toxic to demons and also to vampires. It can be used to flush out the beginnings of vampire infection, to save someone who has ingested vampire blood. (See the Bestiaire Part II, Chapter 4, for more details.) Faeries, on the other hand, can stand its presence and its touch but will be made severely weakened and ill if they can be fooled into drinking it. (Interestingly, werewolves are not affected by holy water at all, just as they are not at all negatively affected by other mundane religious objects.)

That actually is interesting! Ask Luke about.

Many mundane religions include this notion of seraphically aligned water, and it is from the mundanes’ holy men and women that the Nephilim acquire the majority of our holy water. As part of our relationships with mundane religions, we maintain connections with monastic orders across the globe. One of these orders’ responsibilities is to bless water and other objects for the Nephilim. The orders connected to the Nephilim tend to be among the more secretive monastic orders, often those sworn to silence, and the relationships are often kept up by Silent Brothers and Iron Sisters.

How we collect, store, and distribute all this holy water to the Institutes and to Idris is a fascinating hydrodynamic engineering problem that will not be gone into in this text. Those who are interested in more depth are encouraged to visit the Silent City, where the research Brothers there will be more than happy to supply you with the multivolume handwritten tomes they have created specifying the processes, for perusal at your leisure.

No need to be sarcastic, Codex.

I think that’s sincere, actually.


Black for hunting through the night

For death and mourning the color’s white

Gold for a bride in her wedding gown

And red to call enchantment down.

White silk when our bodies burn,

Blue banners when the lost return.

Flame for the birth of a Nephilim,

And to wash away our sins.

Gray for knowledge best untold,

Bone for those who don’t grow old.

Saffron lights the victory march,

Green will mend our broken hearts.

Silver for the demon towers,

And bronze to summon wicked powers.

—Old Nephilim children’s rhyme

One’s first set of Shadowhunter gear is, for most Shadowhunters, an important moment in their training—the time when they begin to first look like other Shadowhunters. When you wear gear, you become part of a tradition joining Shadowhunters across hundreds of years; our gear has remained basically unchanged since modern textile methods came into being.

Battle gear is crafted of a well-processed black leather, created by the Iron Sisters in their Citadel, stronger than any mundane leather and capable of protecting the skin from most demon venoms while still allowing for swift and free movement. Nephilim on regular patrols or similar excursions may choose to wear only the basic gear, but those preparing for battle will often add bracers and greaves, traditionally of electrum (see “Materials” ). Both the gear and accessories such as bracers are typically Marked, both with runes of protection and strength and with more decorative symbols. These might include family crests, Marks commemorating battles, names of angels invoked as protectors, and so on.

The standard Shadowhunter gear involves, for both men and women, simple flat-soled shoes and sturdy, closely fit trousers. For most of Nephilim history gear differed between men and women—men would wear with the above a closely fit waist-length shirt and sometimes a jacket, whereas women would wear a long belted knee-length tunic. This tunic was always a less practical choice, and was worn historically to maintain the standards of modesty and decorum that were required of women as they moved through mundane society. In the past fifty years or so, the use of this tunic has faded in favor of more unified, unisex gear worn by male and female Shadowhunters alike.


Many new Shadowhunters through the years have arrived at their first day of training proudly clad in their family’s ancestral plate armor, as if they were going off to fight the Hundred Years’ War. (Obviously this problem was at its worst during the actual Hundred Years’ War.) In truth this kind of heavy armor is not very useful to Nephilim; standard fighting gear is preferred, and the specifics of the gear are less important than one’s weaponry. The mundane world went through a complicated “arms race” through the Middle Ages regarding armor. Both weapons and armor gradually improved in effectiveness, with new weapons designed to pierce armor, and then new armor designed to withstand those weapons. Armor reached its apex with a somewhat ridiculous full suit of steel intended to stop a blade or an arrow, and became rapidly irrelevant with the advent of artillery and firearms in mundane warfare.

Shadowhunters never participated in this silly exercise. First, Shadowhunters have always, by necessity, prioritized such attributes as freedom of movement, detailed assessment of the environment, and swiftness over raw strength of material, and as a result were rarely tempted by heavier, bulkier armor. Second, the fact is that mundane armor is designed to protect the wearer from the attacks of other mundanes. We, on the other hand, frequently face foes who wield magic, and who might on any given day attack us with fire, with excoriating acid, with bolts of demonic lightning, with venoms and poisons of all kinds. We know of no material—including adamas—that can keep a Shadowhunter safe from all of the devices at the disposal of our demon foes. We therefore have always had to learn to avoid harm by our wits and reflexes, since no amount of steel covering our bodies would truly keep us safe.

Shadowhunters do not typically travel heavily loaded with equipment. What they take with them on patrols or investigations must not slow them down very much, or compromise their agility. Thus they typically prefer small tools, lightweight and easily kept in a pocket. Most Shadowhunters will find a set of tools that they will take with them everywhere; it is worth some time considering what tools you find useful to keep on hand. Some common tools are here suggested, and described in detail where necessary.



—Primary weapon

—Two seraph blades

—Ranged weapon (e.g., crossbow, sling) (Optional)

—Stele You’re kidding. Lame. Okay. Custom lesson from Jace here. Yes, take all that stuff.


Actually, carry two witchlights. Some other stuff that I always carry with me on patrol: chalk. A multi-tool with screwdrivers and two knives and a corkscrew and all that. A sturdy watch. A strong folding utility knife. A butane lighter. A phone.


If you are also carrying a backpack, I recommend throwing in nylon rope, a small crowbar, binoculars, a basic first aid kit, a spare stele, two extra seraph blades. Oh, and rubber gloves. Every so often you’ll be very glad you have them.


The Sensor is a common Shadowhunter device for detecting demonic activity. Sensors have varied in design over the years, but today the Sensor is usually a small handheld oblong made of a black metal. It bears some resemblance to a modern cellular phone or other handheld mundane communication device, but where that mundane device would have control buttons and switches labeled in a mundane language, the Sensor is labeled in Marks whose meaning must be learned. The original Sensor was invented in the late 1880s by Henry Branwell and for a time revolutionized the pursuit and capture of demons. It’s a tricorder.

What? What is a tricorder? Three . . . cords?

Unfortunately, the Sensor is somewhat limited in what it is able to sense. It functions as a frequency detector, tuning in to the vibrations that demons create as they pass through the magical ether. These vibrations vary by demon species and change in intensity based on the intensity of demon activity (number of demons, demonic magic in use, etc.). In theory it is possible to create a “frequency table” matching specific demon species to specific frequencies, and in fact much ink and time was spilled in the years following the invention of the Sensor, creating endless tables for “translating” specific demon signals. In the field Shadowhunters almost never have time to consult a table, and it is usually faster and easier for them to learn from experience to recognize demon types by sight. These tables are now considered mostly a historical curiosity.

But we have wasted your time by telling you about them anyway.

These days Sensors are designed not to be manually tuned (though most can be so tuned if the user demands it) but to scan up and down continuously for all demon activity and offer some educated guesses about the causes of any frequencies that appear. Modern Sensors may have mapping systems, proximity alarms, and other colorful features.

The Sensor often baffles new Shadowhunters, mostly because of its control buttons, which are labeled in angelic runes. This is done to allow the device to be used universally around the world, as the Shadowhunters do not share a single common language other than the language of Raziel and the Gray Book.

SENSORS THROUGH THE YEARSThat title makes me sleepy just looking at it.

I have never in my life been bored enough to actually read this sidebar.

The first Sensor used as its warning mechanism a standard mechanical metronome, which in the proximity of demons would begin to clack rhythmically, its speed increasing as the demon and Sensor grew closer together. This metronome sat atop a large wooden box clasped in copper, the copper having been elaborately inscribed with Marks, and a variety of Marked and un-Marked mechanical works inside did the sensing and ran the metronome. The whole contraption sat atop a heavy cart with four wheels that had to be pushed around, since the metronome had to be kept level with the ground at all times and could easily be disrupted by unexpected movements. Various experiments took place through the early twentieth century to try to make the Sensor self-propelled and able to follow a Shadowhunter, patrol an area independently, and so on. These experiments never resulted in any usable innovation, and more often resulted in a dangerously mobile demon-powered cart that might at any moment charge the nearest Shadowhunter with unknown intent, clacking madly because of its extreme proximity to its own sensing apparatus. This failed branch of Sensor evolution fell away from the tree entirely in the 1960s when modern rune miniaturization magic made it possible to create Sensors that could be carried in a trouser pocket.

The Shadowhunter interested in its history can find older models displayed in libraries and museum collections of older Institutes.

Did you Know? No!

The Codex has a different definition of “interesting” than me

Interestingly, the standard runic labels on the Sensor were originally intended as a temporary measure. In his classic memoir of 1910, A Whoops and a Bang: The Shadowhunter of the Modern Age, Henry Branwell hypothesizes a single Mark that could be used to cause the buttons of a Sensor (or anything else) to appear in the native language of the person holding it. Such a Mark is not known to exist, but Branwell was at that time enthusiastically arguing for the use of warlock magic in collaboration with Nephilim Marks to create new and more complex effects, an unpopular position both then and now (although see the Grimoire, Chapter 6, for a discussion of the history of the Portal). This course of Branwell’s experimentation, however, was disrupted when in 1914 he began a long collaboration with the Iron Sisters, the results of which remain secret to this day. The Mark of Translation remains uncreated, and the Sensor remains covered in runes whose meanings must be committed to memory.


The Sensor is a complex tool, and many Shadowhunters struggle with the nuances of its use. Here we attempt to answer those questions that arise most frequently.

Yes, that is what “Frequently Asked Questions” means, thank you.

Can the Sensor be modified to detect werewolves, vampires, and other Downworlders?

It cannot. The Sensor is attuned to the presence of demon energy; while Downworlders all have some demonic magic in them, they are not demons and do have normal human souls. Therefore they will not register on a Sensor.

Can the Sensor be modified to detect only certain kinds of demons?

Yes! This is a lesser-known but useful function of the Sensor that requires no modification. The buttons can be manipulated, using the Marks, to isolate only demons who match a certain set of qualities.

Can the Sensor be modified to detect a specific Greater Demon?


Can the Sensor be modified to detect where I left some object?


When will my Sensor support the Flash rune?

The Flash rune referred to here causes a burst of bright holy light, and rumors have existed for years that the Sensor was going to be modified to be able to successfully hold the Flash rune. Unfortunately, the Flash rune currently causes the Sensor’s normal function to slow down and often stop working entirely. As yet, the only Sensors available do not support Flash, and only the Iron Sisters know whether they ever will.

Help, my Sensor’s buttons are all labeled in runes.

Those are Marks.

I haven’t learned these runes yet!

We might recommend a trick long known to Shadowhunters, involving drawing your own labels on the Sensor buttons with a felt-tip marker.

My Sensor is vibrating!

That is within the normal bounds of Sensor operation. When a Sensor is overloaded with the proximity of demon energies, it will begin to vibrate with intensity. This was long considered a deficit in the design of Sensors, but the advent of modern technology has caused many Shadowhunters, especially those more familiar with the mundane world, to regard the vibration as a useful feature.

Unlike the mundane tools that vibrate, the Sensor can become so overloaded with demon energies that it can ignite and explode. Therefore, caution is advised.

My Sensor has vibrated so much that it has ignited and exploded.

You will, unfortunately, need to requisition a new Sensor from your Institute. Also, there is a tremendous quantity of demonic energy in your immediate vicinity. You must make sure to evaluate your immediate circumstances before trying to examine your Sensor; it is possible that you are about to be devoured by either a Greater Demon or a Portal to Hell.

So if you had a human who’d drunk a lot of Greater Demon blood when he was a baby, would he set off a Sensor?

Who would do such a terrible thing.

Just hypothetically.

If you already know this guy, track him down! Sensors are for demons you don’t already know personally!

God, get a room, you two.

Good point.


The stele (pronounced in English 'steh•lay) is listed here among the tools of the Shadowhunter but could just as easily be mentioned among weaponry; it is the fundamental tool of the Nephilim, the device by which Marks, our only magic, may be inscribed. An elaborate decorated stele is often the first tool given to a young Shadowhunter at the beginning of her studies.

The stele is a wandlike instrument, made of pure adamas. It is inert when not in use but when taken up glows and warms with the magic of the Marks. It is longer than modern writing instruments, usually a foot long or more, and as a result contemporary Shadowhunters will require practice to be able to draw runes with facility when using one.

All steles are functionally identical, but of course there is wide variation in their design. Many have handles inscribed with family crests and the like, some are studded with gems—the only requirement for a working stele is that it include an unbroken rod of adamas of at least a certain length. On the other end of the spectrum are the narrow practice steles given to child Nephilim to learn runic manuscription on sheets of parchment.

The first stele is believed to have been a rough oblong of adamas used by Jonathan Shadowhunter to inscribe the first Marks on his own skin. The stele designs have become refined over the years. Some scholars see a link between the stele and the Jewish yad, the ritual pointer used to avoid physically handling the parchment of the Torah when reading from it, but no direct connection can be made, although it is probable that the earliest Iron Sisters were inspired by such designs. Represent!

Demons are not harmed by exposure to a stele, but they will typically recoil from one, as they will recoil from all adamas.


One of the great secrets kept by the Iron Sisters is the precise manner by which adamas is extracted and purified from its ore. What we do know, however, is that the presence of adamas affects the rock from which it is extracted, and though it is simple rock, it gives off a pure white glow, as though reflecting the light inherent in the adamas. These “sister stones” of adamas are broken up and polished by Iron Sisters, and Marked to make their glow a property that can be turned on and off at the will of the Shadowhunter holding them. Most rune-stones are basic and interchangeable, and rarely do Shadowhunters get attached to a particular stone over any other. All Shadowhunters carry a witchlight stone, to remind them that light can be found even among the darkest shadows, and also to supply them with actual light when they are themselves literally among dark shadows.

The great advantage of witchlight stones is that their glow never fades or dissipates, for no fuel is being consumed in creating their light. Such a stone can, however, be destroyed by pulverizing it into dust, whereupon the angelic light absorbed into it will dissipate; thus one never finds “witchlight sand” or the like.

The largest single witchlight crystal in the world can be found in the Silent City in the form of the Angelic Colossus, a representation of the Triptych, the familiar motif of Raziel ascending from the water wielding the Mortal Instruments. The crystal stands roughly thirty feet tall, and it guards (and lights) the entrance to the Silent Brothers’ living quarters. The Colossus is rarely seen by anyone other than the Silent Brothers, however, and those interested in large installations of witchlight are encouraged to visit the Institute of Cluj, where the renowned Vampire Arch forms the threshold to the Institute. For many years it was thought that humans infected with vampirism were sensitive to natural and holy light and would recoil from it; the Arch was built under the belief that it would protect the Institute from infected humans. We now know this not to be true, but the Arch remains as a symbol of the Cluj Institute’s dedication to the Angel.

Or maybe they just like hurting vampires a lot.

Definitely that. Those Cluj guys are crazy.

See this is why you are a useful teacher. I get the inside scoop.

I believe I mentioned something about you two and a room a few pages ago?


1. What’s your everyday carry? What might you add to it to cover your new Shadowhunter responsibilities?

Wallet, watch, phone, stele, pencils, sketchbook, waterproof fine-tip pen for inking, pencil sharpener, witchlight, mint lip balm.

I hear chapped lips are a leading cause of death in Shadowhunters. My turn! Wallet, watch, phone, bass picks, pens, notebook, dice of various kinds, little cloth thingie to clean glasses with—except I don’t wear my glasses anymore, huh, I guess I don’t need to carry the cloth around anymore—super-nerdy pocketknife. Aaaand lip balm. Don’t even lie. You reek of strawberry right now.

2. What weapon might you like to specialize in? What about it draws your attention? Alas! My secret shame revealed!

Go ahead, say “rapier wit.” I know you want to.

RAPIER WIT FINE YES that is what I was going to say because I am so funny. Poor Simon.

Anyway, I have no idea of an answer to this question, and frankly, Codex, this kind of question is the least of my problems right now. I would like to specialize in not being nearly killed yet again.

I would like to specialize in being an immortal invulnerable killing machine who craves the blood of the living.

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