Introduction
Glyph of Warding is among the most interesting and versatile options available to defend a fixed location. It’s not easily useful for adventuring spellcasters, but the ability to bind spells to an arbitrary condition is incredibly powerful.
A deep read of the spell reveals some horrifying rules implications. The spell’s triggers are essentially limitless, range does not appear to matter, and there’s nothing stopping a spellcasting from creating a near-limitless quantity of glyphs except the 200gp material component. Ambitious spellcasters could easily use this to break reality.
Table of Contents
Glyph of Warding Spell Description
| Level | Casting Time | Range/Area | Components |
| 3rd | 1 Hour | Touch | V, S, M* |
| Duration | School | Attack/Save | Damage/Effect |
| Until Dispelled or Triggered | Abjuration | Dex save | Various |
Single-use, permanent, but slow enough to cast that players are unlikely to cast it while roaming dungeons. This is clearly intended for a place that a caster intends to protect long-term.
When you cast this spell, you inscribe a glyph that later unleashes a magical effect.
Flavor text.
You inscribe it either on a surface (such as a table or a section of floor or wall) or within an object that can be closed (such as a book, a scroll, or a treasure chest) to conceal the glyph.
You can clearly hide the glyph, but still have it take effect. Line of sight between the glyph and the target doesn’t appear to be necessary, so you could put the glyphs behind walls, under floor tiles, inside books with boring titles like “Cooking Soup: A Practical Guide”, or wherever else you would like. Technically, the glyphs may not need to be on or near whatever you’re attempting to protect, as we’ll see below.
The glyph can cover an area no larger than 10 feet in diameter.
This does not matter. In fact, you want your glyph to be as tiny as possible so that you can fit more glyphs into the same area. Fitting a bunch of microscopically small glyphs onto an item or a wall or whatever is ideal.
If the surface or object is moved more than 10 feet from where you cast this spell, the glyph is broken, and the spell ends without being triggered.
This prevents players from hauling the glyph around with them or sending exploding runes by mail. You might be able to put a glyph on an item and carry it around within a room safely, but that’s all.
The glyph is nearly invisible and requires a successful Intelligence (Investigation) check against your spell save DC to be found.
This keeps your glyphs easily hidden, but a high-level caster’s save DC might be as high as 18 before considering magic items, and even a DC of 18 can still be bypassed by characters with poor modifiers. Enough peasants peering around the room will quickly identify your glyphs.
You decide what triggers the glyph when you cast the spell.
Cool.
For glyphs inscribed on a surface, the most typical triggers include touching or standing on the glyph, removing another object covering the glyph, approaching within a certain distance of the glyph, or manipulating the object on which the glyph is inscribed. For glyphs inscribed within an object, the most common triggers include opening that object, approaching within a certain distance of the object, or seeing or reading the glyph.
This is essentially flavor text and/or advice. It is not a mechanically binding piece of text. You can ignore it entirely, but it would be polite to limit yourself to the examples provided here because if you go beyond those examples, things get out of hand almost immediately.
Once a glyph is triggered, this spell ends.
“Permanent until trigger or dispelled.” Makes sense.
You can further refine the trigger so the spell activates only under certain circumstances or according to physical characteristics (such as height or weight), creature kind (for example, the ward could be set to affect aberrations or drow), or alignment.
This is extremely generous wording, allowing you to set glyphs to trigger under incredibly specific circumstances, even using non-observable things like alignment. You’re free to metagame here, essentially.
Example: “Trigger the glyph when a chaotic evil humanoid walks through the front gate of the city.”
You’ll note that this satisfies all of the above restrictions, but says nothing about where his rune might be.
You can also set conditions for creatures that don’t trigger the glyph, such as those who say a certain password.
A spellcaster making use of Glyph of Warding is almost certain to have a password or some other means to bypass their glyphs. If they have allies, they might share that precious secret with those allies. This creates a possible way for enemies to bypass the glyph, too.
Security by obscurity isn’t reliable. Two people can keep a secret if one of them is dead (well…). If there is a way to safely bypass your glyphs, it’s not a matter of “if” someone will bypass them, it’s a matter of “when”.
When you inscribe the glyph, choose explosive runes or a spell glyph.
Self-explanatory.
Explosive Runes. When triggered, the glyph erupts with magical energy in a 20-foot-radius sphere centered on the glyph. The sphere spreads around corners. Each creature in the area must make a Dexterity saving throw. A creature takes 5d8 acid, cold, fire, lightning, or thunder damage on a failed saving throw (your choice when you create the glyph), or half as much damage on a successful one.
The variable damage type is great. I recommend sticking to Thunder by default. However, Fireball does more damage and scales better, which makes it pretty clear that there are better options available even if all that you want is damage.
Notably the explosion is centered on the glyph, which is a restriction not faced by the Spell Glyph option, tipping the scales even further in favor of using essentially any spell rather than Explosive Runes.
Spell Glyph. You can store a prepared spell of 3rd level or lower in the glyph by casting it as part of creating the glyph.
This is where we get into abuse cases.
The spell must target a single creature or an area.
This limits our options. No multi-target spells like upcasting Hold Monster, but Hypnotic Pattern and Fireball work fine. Also no spells with a range of Self, such as Armor of Agathys.
The spell being stored has no immediate effect when cast in this way. When the glyph is triggered, the stored spell is cast.
Pretty simple on its face, but it does raise a few edge cases.
What happens with spells which require ability checks or attack rolls? For example, if I put Dispel Magic into a glyph, but my ability scores later change, what happens? As a DM you could rule that the caster uses whatever stats and state they were in when they created the glyph, but then the caster is encouraged to have allies cast Enhance Ability and Guidance. You could rule that you use the caster’s stats at the time that the glyph triggers, but what if the caster is dead or the subject of Feeblemind? Neither option is especially satisfying, and either one creates abuse cases.
If the spell has a target, it targets the creature that triggered the glyph.
This sentence is a problem. The limitations for triggers are basically non-existent, which means that you can target creatures essentially wherever you want. “The BBEG eats food” is a perfectly valid trigger.
If the spell affects an area, the area is centered on that creature.
On its face, this appears to say that the triggered spell doesn’t care about range; it simply targets the creature and that is that. The rules for range for spells don’t really account for this. As written, the glyph doesn’t need line of sight and can be triggered at any range. RAW, you could use Glyph of Warding to drop Fireball into someone’s house from another plane of existence, and that can’t possibly be what the designers intended.
The handling for area effects is similarly vexing. What do we do with cones? It’s an area, so the area is centered on the target, but at what orientation? What about spells like Wall of Stone, which explicitly can’t occupy the same space as a creature? Would Wall of Stone simply fail? I’m not certain. I certainly would like to be able to put up a Wall of Force when someone tries to kick open my front door.
If the spell summons hostile creatures or creates harmful objects or traps, they appear as close as possible to the intruder and attack it.
This seems to be a specific exception to the “must target a single creature or an area” limitation. Since the glyph handles concentration, you’re free to cast the best summon spell that you can get and let your summoned wall of cows handle the problem.
If the spell requires concentration, it lasts until the end of its full duration.
This is fantastic. Spells like Web and Evard’s Black Tentacles are a great way to pin enemies in place while other glyphs trigger and kill them or alert you to their presence or whatever else.
You can also use Glyph of Warding to apply concentration buffs to a target, which is neat. It’s an expensive way to solve that problem, but against a particularly tough enemy that might be just what you need.
At Higher Levels. When you cast this spell using a spell slot of 4th level or higher, the damage of an explosive runes glyph increases by 1d8 for each slot level above 3rd. If you create a spell glyph, you can store any spell of up to the same level as the slot you use for the glyph of warding.
Glyph of Warding never becomes obsolete. Notably this does make it hard to put spells of 8th and 9th level into a glyph because you never get a second spell slot of those levels. Your DM might allow you to use a spell scroll, but more likely you’ll be limited to 8th-level spell glyphs. Honestly, that’s plenty.
* – (incense and powdered diamond worth at least 200 gp, which the spell consumes)
We won’t be spamming this. 200gp adds up quickly.
Stacking and Chaining
The effects of different spells add together while the durations of those spells overlap. The effects of the same spell cast multiple times don’t combine, however. Instead, the most potent effect — such as the highest bonus — from those castings applies while their durations overlap, or the most recent effect applies if the castings are equally potent and their durations overlap.
The rules for combining magical effects present a weird question here. Can we trigger multiple glyphs from a single event?
It seems reasonable that you can’t have multiple glyphs cover the same physical area. However, glyphs aren’t limited to affecting what is inside the area of the glyph.
So could we have multiple glyphs which trigger from the same event? Could I cover the walls in glyphs that cast Fireball and have them all trigger in sequence until the intruders are dead? I think the answer is “yes”, which is terrifying. Even if we can’t, we can make one trigger dependent on another glyph.
For example: A paranoid lich is warding their favorite lair. They set three spell glyphs to cast hold monster when a creature crosses a specific point. Why three of these glyphs? Just to make sure that one of them sticks. They then set some arbitrary number of spell glyphs to cast 8th-level Scorching Rays on any paralyzed, living creature in the hallway.
An adventurer walks in, is paralyzed if they fail any of the three saves, and is then machine-gunned into a pile of ash. Glyphs trigger until the target is dead or the glyphs run out, but stop when there is no longer a paralyzed, living target, so the remaining glyphs remain in place for the next paralysis glyph trap a few steps further down the hall.
Spell Rune
I won’t cover every single spell that could work with Glyph of Warding because it’s not especially helpful beyond the advice provided in our spell list breakdowns. Your best bet is to use multiple save-or-suck effects to guarantee success, chain runes to eliminate incapacitated targets, and summon creatures to clean up whatever’s left.
That said, there are a few unique cases to consider.
Counterspell
Glyph of Warding can be dispelled. This presents a problem, because a sufficiently dedicated and patient spellcaster can eventually wear through all of your glyphs, stopping only to rest and restore spell slots. To counter this, you can put Counterspell into a Glyph of Warding.
You might then think “what if the target tries to counter my Counterspell?” Well, that’s simply not allowed. Counterspell targets the creature casting the spell, and you’re not there.
Dispel Magic
Enemies might walk into your secret base covered in magical protections and ready to fight. Glyphs that repeatedly hit them with Dispel Magic will melt through those buffs, leaving them exposed. They might retreat and come back re-buffed on another day, but that leaves you time to counterattack while they’re resting. They’ve already burned resources to buff, while you might be totally fresh.
Raise Dead, etc.
Any spell which raises you from the dead could be put into a Glyph of Warding, though keep in mind that you’ll need to spend the material component when you put the spell into the ward. This is a weird, expensive way to solve the same problems solved by Death Ward or Clone.
Wish
If you can find a way to cast two 9th-level spells, Wish has an interesting interaction with Glyph of Warding. You must cast the spell at the same time that you cast Glyph of Warding, but the spell doesn’t take effect until the glyph triggers. This includes the drawbacks for casting Wish, as well as the risk of not being able to cast Wish again.
To maximize the benefits here, deplete the world’s supply of 9th-level spell scrolls of Glyph of Warding and of Wish and set up a new glyph every day with a different effect but the same trigger across each glyph. When you’re satisfied, trigger all of your glyphs at once. You’ll almost certainly lose the ability to ever cast Wish again, but it may be worth the price to have permanent resistance to every damage type.
I would absolutely not allow this in my own games, of course. This is silly.
Conclusion
Glyph of Warding’s text is overly permissive to the point that it breaks the internal consistency of the game. If you’re going to use it, you need to put up guard rails. I recommend three changes:
- Limit triggers to observable phenomena occurring on the same plane of existence, and don’t allow the use of more than one adjective unless it’s to include a single way to bypass the glyph (password, etc.). This prevents the triggers from becoming overly convoluted or specific, and prevents problematic chain effects like the Hold Person+Damage combo I suggested above.
- Limit glyphs to targeting creatures inside the glyph’s area, which neatly solve the “fireball the other side of the planet” abuse case while also giving a reason for the glyph to have a maximum size. You might need to make an exception for glyphs placed on or inside objects.
- Limit spell glyphs to using range and line of effect measured from the center of the glyph. This solves the issue of AOEs like lines and cones while also preventing numerous abuse cases.
With those changes in place, Glyph of Warding might not break your game. No promises, though.
