Spotting glyph of warding

[Beltas]

I’m hoping for advice on how to balance smart NPCs against player agency.

Glyph of warding strikes me as the sort of spell that smart NPCs would generally use to protect a high-value location. My reading of the spell is that it can be cast in such a way that by the time it is possible to spot the glyph it is too late. This is frustrating to my players who feel like they should be able to roll some dice to detect the glyph before it is triggered. I avoided the HP tax versions that will do some damage even on a save but it still resulted in grumbling.

If NPCs use this spell in your campaign, how do you handle detection/avoidance by player characters?

[No brains]

It depends on the kind of group you have.

If you have a party that feels like basically being careful and saying, "I check for traps" should cover it, then the DM can describe the rogue using special pliers to open the book and look with a mirror so they can see a glyph in a book without being able to 'read' it. In some game settings, it makes sense that a trap-checker would be that next-level paranoid.

On the other hand, some players appreciate tests to their paranoia. If they know that some book has some glyph on it somewhere, they're not going to feel vindicated until their caution pays off. They're going to try every little move until they realize that the book has a tripwire on it that will snap and then drop a tapestry blocking the glyph and they need to glue down the string and then cut it from the book so that they can get out safe.

A middle-path idea is to make a trap do less damage the more byzantine it is to stop. The glyph on the floor out in the open can cast meteor swarm, but the glyph under that glyph concealed by an illusion that gets dispelled with the first glyph should only do something like a low level magic missile.

[DarkKnightJin]

I’m hoping for advice on how to balance smart NPCs against player agency.

Glyph of warding strikes me as the sort of spell that smart NPCs would generally use to protect a high-value location. My reading of the spell is that it can be cast in such a way that by the time it is possible to spot the glyph it is too late. This is frustrating to my players who feel like they should be able to roll some dice to detect the glyph before it is triggered. I avoided the HP tax versions that will do some damage even on a save but it still resulted in grumbling.

If NPCs use this spell in your campaign, how do you handle detection/avoidance by player characters?

If the players have access to certain tactics, so do the NPCs.
If the BBEG gets a Glyph of Warding around a corner to warn of intruders, that's perfectly fine.
Some enemies are smart enough to realize "I could place it on the ground and anybody could see it. I could also place it just around the corner in the only access hallway, and they'd inform me of their approach without it being foiled instantly."

[MaxWilson]

I’m hoping for advice on how to balance smart NPCs against player agency.

Glyph of warding strikes me as the sort of spell that smart NPCs would generally use to protect a high-value location. My reading of the spell is that it can be cast in such a way that by the time it is possible to spot the glyph it is too late. This is frustrating to my players who feel like they should be able to roll some dice to detect the glyph before it is triggered. I avoided the HP tax versions that will do some damage even on a save but it still resulted in grumbling.

If NPCs use this spell in your campaign, how do you handle detection/avoidance by player characters?

I have two kinds of traps: (1) D&D-style "fun" traps, created by trap gremlins, which are designed to be interesting and dangerous but avoidable, and (2) security measures designed to keep something safe by killing or capturing whoever set it off.

Glyph of Warding is the latter kind of trap, and I handle it by letting them know that the target (e.g. an archmage) is serious about security. Maybe she's got a reputation, maybe there are big signs at the entrance to her tower that says "If you go through this door uninvited you will die," but in either case I will try to telegraph the danger, and then for the most part I don't have to worry about it because then the players leave that archmage alone and stick to dungeon crawls and "fun" trap gremlin traps.

If I had to break into an archmage's tower as a PC, I'd probably rely mostly on Tiny Objects + Nystul's Magic Aura to set off traps ahead of me, plus judicious Detect Magic, not by trying to beat the Investigation DC of the trap once the glyph is visible. Obviously if I do happen to spot a glyph I'll Dispel it, but as you say, it's easy to set the glyph trigger such that by the time you see it, it is too late.

TL;DR I mostly handle it by warning players to stay away, but if they do it anyway I'll just do what is logical for whoever cast the spell.

[darknite]

Traps suck. Smart enemies will use traps. Glyphs are traps.

By the by... My game this weekend opens with a party transferring through a portal who's destination is on a Symbol of Death that triggers unless a password is used. This portal is the main entrance to a Liches' domain and requires major defenses. I plan on going around the table and asking each player what they do as they pass through the portal, giving them 15' of movement on the far side due to the complication of passing through the gate.

The Symbol requires a DC 20 Intelligence (Investigation) check to spot - this will be at Disadvantage if players don't actively use an Investigation check as they pass through, which will reduce their passive Investigation by 5. If the Symbol is spotted and pointed out a caster who hasn't yet acted can attempt to Dispel Magic the Symbol (DC 18) or anyone can try to say a password (but since they don't know this the odds of that happening are beyond reasonable probability). Otherwise it goes off after the last PC passes for 10d10 Necrotic Damage (Con Save DC 20 for half). Then we roll for initiative as the necrotic-immune guardians move in to attack.

[Man_Over_Game]

I mean, wouldn't Detect Magic work? It's a level 1 Ritual, I'm sure SOMEONE in the party is capable of casting it.

If you're searching the secret office of a dungeon, you don't NOT cast Detect Magic.

[darknite]

I mean, wouldn't Detect Magic work? It's a level 1 Ritual, I'm sure SOMEONE in the party is capable of casting it.

If you're searching the secret office of a dungeon, you don't NOT cast Detect Magic.

Yeah, that should work (things that block Detect Magic notwithstanding).

[StoicLeaf]

detect magic won't spot a concealed glyph of warding, though.
I.e. cast it on a wall, hang a nice carpet over it.

@OP:
It would help to have more information but from the sounds of it your players don't want to be creative, they want to, as you put it, roll some dice and have the problem go away. I don't think you'll ever get traps to work for this group.
For poops and giggles, however, should your players ever cast a glyph of warding themselves, have the person it was cast for enter the room, roll some dice and poof! The glyph disappears! ;)

[Man_Over_Game]

detect magic won't spot a concealed glyph of warding, though.
I.e. cast it on a wall, hang a nice carpet over it.


Uh....

"This spell can't detect magic through 1 foot of stone, 1 inch of common metal, a thin sheet of lead, or 3 feet of wood or dirt. "

[Beltas]

detect magic won't spot a concealed glyph of warding, though.
I.e. cast it on a wall, hang a nice carpet over it.

@OP:
It would help to have more information but from the sounds of it your players don't want to be creative, they want to, as you put it, roll some dice and have the problem go away. I don't think you'll ever get traps to work for this group.
For poops and giggles, however, should your players ever cast a glyph of warding themselves, have the person it was cast for enter the room, roll some dice and poof! The glyph disappears! ;)

Yep. Detect magic is trivially easy to block.

First time I had NPCs use the spell, it triggered sickening radiance in the entry area which delayed the party and gave the enemy time to prepare. The party had suspected a trap and rolled investigate ([edit] they got a very good roll so they were feeling good), but they couldn’t see the glyph from their vantage point so I ruled they found nothing. When they went forwards and triggered the glyph, there were grumblings.

They’re about to raid a treasure vault and I’m considering the spell again. This time around, my plan is to hint that they need some mcguffin to safely access the vault. If they try to access the vault without it then I feel justified in creating a glyph placement that they likely won’t be able to otherwise thwart. Is that unreasonable?

[Man_Over_Game]

Yep. Detect magic is trivially easy to block.

First time I had NPCs use the spell, it triggered sickening radiance in the entry area which delayed the party and gave the enemy time to prepare. The party had suspected a trap and rolled investigate, but they couldn’t see the glyph from their vantage point so I ruled they found nothing. When they went forwards and triggered the glyph, there were grumblings.

They’re about to raid a treasure vault and I’m considering the spell again. This time around, my plan is to hint that they need some mcguffin to safely access the vault. If they try to access the vault without it then I feel justified in creating a glyph placement that they likely won’t be able to otherwise thwart. Is that unreasonable?

I dunno if you read this, but..


Uh....

"This spell can't detect magic through 1 foot of stone, 1 inch of common metal, a thin sheet of lead, or 3 feet of wood or dirt."

On the vantage point aspect, you have to ask yourself what's more important: The Game, or The Narrative?

The Narrative is important to keeping the world fleshed out and real. Casters cover their Glyphs in lead to ensure that thieves can't track it easily.

The Game is important to ensure that players are capable of controlling the environment, and that they're punished for their mistakes. If The Game portion is important, what was the proper response that the players should have made to disarm the trap? What mistake did they make to deserve it blowing up? And are those expectations realistic?

Some people might expect a punishing realistic narrative, where the underdog doesn't win and the powerful are overly cautious. But it's important to remember that not everyone plays that way. A DM with a party of 5 is still just one person out of 6.


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Personally, I think a good Investigation check, combined with a Detect Magic, should be enough to locate a Glyph of Warding in almost every circumstance, period. Unless there were clues to set expectations of the players' actions regarding the trap, I shouldn't expect the players to do anything more than that to control that particular scenario.

Generally, every problem should be solvable with the right tools. The more clues that are provided, the harder the resulting scenario should be. By the time the players reach a highly lethal trap, they should have received enough clues to realistically be able to avoid or defang it.

Or, in a way, Difficulty = Knowledge + Strength.


If the players are going to encounter a lich at a low level, they are going to receive lots of warnings and suggestions on how to deal with the matter. If the players are a high level, a well hidden trap might catch them off guard when they can afford to take the hit. Generally, players should only die as a punishment for a lack of possible preparation, and that "possibility" of preparation requires them to first have knowledge of how to prepare. Surprising a table is always an option, but it should almost never be a fatal encounter, but merely a setback with the larger goal of attrition (unless the players ignored caution and deserved the ambush).


In your example, the high difficulty seems unbalanced compared to the amount of knowledge or the capabilities of the players to deal with the problem.



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TLDR: Ask yourself: What did your players do wrong to deserve that? If the answer was "Nothing", then the mistake is yours.

If you can't blame the players, you have to blame yourself. That's probably one of the best things a DM could learn.

[MaxWilson]

First time I had NPCs use the spell, it triggered sickening radiance in the entry area which delayed the party and gave the enemy time to prepare. The party had suspected a trap and rolled investigate, but they couldn’t see the glyph from their vantage point so I ruled they found nothing. When they went forwards and triggered the glyph, there were grumblings.

This was probably just a miscommunication. They thought they were "rolling Investigation" to see if there were any glyphs or traps, but the actual action they were taking was apparently just carefully examining their surroundings without moving (in case that would trigger a glyph). Maybe next time you will need to be more explicit:

"Without moving, you carefully look around the room, trying to see if there are any glyphs or wards hidden in the nooks and crannies of the walls. Please roll Investigation. [roll, roll, announce total] From where you are standing, you are pretty sure that none of the things you can see are concealed magical glyphs. Do you want to poke your head around the corner to look for glyphs there?"