D&D 5E How to deal with a Warlock gaining Detect Magic as a cantrip

[Oofta]

I really like the image of a warlock seeing things that the "normals" don't see. The warlock's world is strange and mystical, filled with colours that don't actually exist. It fits the theme of someone who has made a pact with an otherworldly entity.

As the posters above have said, detect magic is not overpowered.

It is not "detect invisible". If someone magically invisible comes within range, all the warlock knows is, "you sense magic." If someone is wearing a magic ring under a glove, all the warlock knows is "you sense magic."

If the warlock can't see the item or person then they see no aura and cannot determine the college. If they see no aura then they don't even know where the person or item is.

A GM might give the player some information over and above what the spell provides (like the direction or intensity of the magic) but RAW all the spell actually tells the caster is "there is 1 or more magics in range."

Finally, and this needs to be stressed, detect magic requires concentration. This is a precious game mechanic which all the really useful effects use. If the warlock's player chooses to spend their concentration slot of detect magic instead of hex, reward them for it.

You do point out something - detect magic will probably always be detecting magic with most parties. Someone in the party have a magic sword? You know there's magic within 30 feet.

Unless you are spending actions every round to locate specific items, it doesn't tell you much.

 

[Horwath]

Let the player shine.

As other stated, it's a limited resource pool for warlock.

If he takes it at 2nd level then he is delaying Repeling blast, Agonizing blast, Devil's sight and other more usefull invocations by 2 or 3 levels.

And if he takes is as 5th or 6th invocation you have no problem as at lvl10+ seeing magic is no big thing. I mean you are flying around and teleporting...

 

[CydKnight]

If I had a player that insists they will spam Detect Magic, Perception Check, etc. ad nauseam, I will find something to nerf it in game. Antimagic Field, Feeble Mind, and similar spells don't exist only for player characters.

 

[Mistwell]

If I had a player that insists they will spam Detect Magic, Perception Check, etc. ad nauseam, I will find something to nerf it in game. Antimagic Field, Feeble Mind, and similar spells don't exist only for player characters.

Why would you do that though? What's so wrong with always detecting magic and looking around as a character concept for your games, instead of taking one of the other options?

 

[Warmaster Horus]

Sounds like a handy person to have around. As others have said it needs an action to use properly. Makes using Active Perception (requires action) and Detect Magic (requires action) hard to use at the same time, possibly.

 

[CydKnight]

Why would you do that though? What's so wrong with always detecting magic and looking around as a character concept for your games, instead of taking one of the other options?

I am advocating doing this within the rules as written because I feel it's my job as a DM to do such things within the rules to keep the game challenging for the PCs. They can in turn find a way to counter my counter if they wish. It's not like I am proposing a house rule forbidding it outright.

 

[Mistwell]

I am advocating doing this within the rules as written because I feel it's my job as a DM to do such things within the rules to keep the game challenging for the PCs. They can in turn find a way to counter my counter if they wish. It's not like I am proposing a house rule forbidding it outright.

But the game challenges are not primarily either "find a way to counter a PC's special ability which is one of their few limited resources" nor is it typically "hidden magic is a key to challenging PCs which is spoiled by detect magic".

Would you be looking for ways in the rules to make his offensive magic less harmful if he had chosen that option instead? It seems like you're kinda metagaming it a bit to act as a DM competitor. Why not roll with it and reward the player's use of detecting magic instead of choosing combat-oriented abilities?

 

[Corwin]

"Adversarial DM" is a valid playstyle. As long as everyone at the table has buy-in, all good AFAIC. Heck, I'd say that playstyle has its roots in the early origins of the RPG hobby. Not by bag these days, but who am I to judge?

However, given that, I do not believe such a playstyle should include arbitrary handwavium invalidation. A DM should challenge and confront the PCs within a fundamental degree of "fairness", IMO. Because the DM has infinite power to hose the PCs or gimp them on a whim, I believe it is incumbent upon them to keep themselves in check. I guess what I'm saying is, be an adversary to the characters, not the players. If you get my drift...

 

[Warmaster Horus]

As others have mentioned there are some pretty easy ways to obfuscate items or areas from Detect Magic. Covering with sufficient material or Nystul's Magic Aura both come to mind. Use those instead of nerfing a PC's earned abilities.

 

[Mistwell]

However, given that, I do not believe such a playstyle should include arbitrary handwavium invalidation. A DM should challenge and confront the PCs within a fundamental degree of "fairness", IMO. Because the DM has infinite power to hose the PCs or gimp them on a whim, I believe it is incumbent upon them to keep themselves in check. I guess what I'm saying is, be an adversary to the characters, not the players. If you get my drift...

I agree. The orcs don't know the invaders can see magic at whim. Their shaman might make a magical trap not knowing the invaders will spot it with this. Using the rules to find ways to intentionally make it more difficult (or even impossible) to spot with detect magic isn't being adversarial to the characters - it's just plain being adversarial to the players in my view. That player chose to give up other options which, let's be honest, are generally considered much more powerful than this one. Finding ways in the rules to counter the less-powerful and much more situational ability seems adversarial to the player. It just smacks of, "Oooh you made a mistake in character generation by choosing that ability because I, the DM, can think of lots of ways to make it nearly useless! Next time maybe you'll learn to choose a more optimized choice."

On the other hand, if the goblin spy overhears the party talking about how they can see magic at will, the shaman might adjust his tactics to spread magic throughout a room (one one of which is a real trap) to confuse the character and prevent them from easily spotting the trap. That seems like a challenge to the characters, rather than the player.