Wednesday, March 4, 2020

Going Through the Spells: Detect Magic

Art by Publisher’s Choice Quality Stock Art ©Rick Hershey Fat Goblin Games

Detect Magic is one of the most used utility type spells. Gold and gems are great, but let's face it, we're going into tombs to grab the magical trinkets hidden behind secret doors, protected by deadly traps, and worn by those who have no interest in giving them up. It's straight forward.

Old School Essentials Mechanics
Duration: 2 turns
Range: 60'
Enchanted objects, areas, or creatures are caused to glow. Both permanent and temporary enchantments are revealed.

Another unspecified glow effect. Again, no real specification if everyone sees the glow or only the caster. Again, with these types of spells I default that only the caster can see the glow.

I am curious  why Detect Evil last for 6 turns and have a range of 120'. Is evil easier to detect than magic?

Here's the aspect of the spell I don't understand and that's the crossover. I mean it might be ticky tacky, but why would a cleric have the spell to detect magic? I understand there are magic items only clerics can use and if a cleric worships a god of magic, but it seems out of the cleric's realm. I'd love to hear what others think about this.

AD&D Mechanics
Duration: 1 turn
Range: 3"
- The cleric detects magical radiations in a path 1" wide, and up to 3" long, in the direction he or she is facing.
- The caster can turn 60 degrees per round. 
- Note that stone walls of 1' thickness, solid metal of but 1/12" thickness, or 3' or more of solid wood will block the spell. 

Wow okay. I need a carpenter to help with all these measurements. It's a shitty description. The entire description focuses on stupid thickness and how it won't work. Focus more on how the spell works. End of complaint. Nope I lied. How many times in an adventure are the thicknesses of walls given? Thickness of a metal chest? I mean 1/12" thickness, really dude?  

And the whole flashlight vision thing make no sense. So the cleric becomes a lighthouse and spins in a circle to attempt to detect magic? 

The most important absence is no information about how the cleric detects the magic. I guess rely on the old tried and true, glow trick. 

I wouldn't use this spell as written. Not at all. The Old School Essentials version is easier to use. You don't even need a ruler. 

However, it does specifically states that only the cleric detects the magic. Bravo. 

Our special guest star system tonight is OSRIC. The mother of the OSR systems! 

OSRIC Mechanics
Duration: 1 turn
Range: Caster
- Creates a tunnel of magical vision in the path of 10' wide and 30' long in which the cleric see the aura of any magical item as a glowing blue nimbus.
- The spell is blocked by solid wood 3' thick, by stone 1' thick, and by solid metal 1" thick. 
- The cleric can only scan 60 degree arc during the course of a round. Turning more quickly does not allow magic auras enough time to form in the cleric's vision.

The description on how the spell works is better in this version. I'm not a fan of measuring the thicknesses. If you can't see it, the cleric can't detect the magic. Boom.

That concludes the third entry into this series. Thanks to everyone who's participated with comments and taken the time to read the posts. It has been an education by taking a closer look at these spells. 


  1. Detection tends to be a metaspell in my game. That is, once you know the basic spell framework, you can prepare a specific instance of it in a multitude of ways (although it may require you to possess a sample of what you are trying to detect when you prepare the spell).

    I tend to effectively use sense [thing] at first level. By concentrating you know the direction and approximate distance to the strongest concentration of the thing within range. You can ignore stuff in the immediate vicinity, stuff you already know about, or stuff outside a certain range (allowing you to search a room for example quite easily). You need to concentrate while doing so (and it lasts as long as you do concentrate on it). Finding something is very similar to dowsing, and it can find things hidden in containers and behind normal walls. It's not really used as a combat spell, and most often enchanted into an actual dowsing rod.

    At second level you generally get to see the thing with see [thing]. The thing becomes visible to you if it is normally not (which is why see invisible is a second level spell). So with detect magic all magical dweomers within range would become visible (if they are not normally). How much information could be extracted from this depends entirely on the nature and training of the viewer. So a magic user can do an analysis of sorcery and a cleric an analysis of blessings (both being classed as "magic" under the D&D rules.

    It does have the limitation that is does tend to rely on the ability that the magic be in plain sight (powerful magics might have an aura that extends beyond the container that it is in [roughly 1" per level would be a good rule]), but does have the advantage that you do get to see and analyse the magics.

    Higher level detects exist, generally in the form of locate object and identify.

    Oh, and sense spells can be used as a trigger for other magic. This is, after all, effectively how magic mouth works. And yes, you could create all sorts of conditions for the trigger to activate when you prepare the spell [sense one-armed man with a blue parrot on his shoulder is a valid detection spell in my game.]

    [Of course the attitude of the religion towards magic would also affect why clerics might have detect magic. After all, magic in the wrong hands is dangerous...]

  2. Perhaps Clerics are granted this spell because they are on a quest to destroy some ancient (magical) evil?