demon identification for dummies

So demons can fool any intellego spell to identify them?

Big problem! Why not use PeVi to identify them?! Create a powerful magical doorway that casts two DEOs on anyone passing through (lvl 25, non-warping) with +52 penetration. Make this the entrance to your covenant. Anyone who comes in gets the spells cast on him/her. Anybody who refuses to pass through stays outside.

Or for the traveling magus: Just cast DEO on any creature you meet. If it reacts, it's infernal. Ideal: Use Sensory magic.


EDIT: And forget the Code of Hermes. If they are affected by DEO, it is clearly not their affair, nor is it scrying (it has no effect unless it has an effect).

Some potential counters. Might or might not work for you

  1. It might be that casting a spell that does not affect the target still causes warping if it is high level spell blasting you. I am unsure if there is a definitive answer to that.

  2. Pissing off demons might not be a good idea. Imagine hell declaring a crusade on the order of hermes. Things might get nasty quite fast. Not añll magi are able to deal with a might 20 demon, let alone thousands of them. Even if the heavy hitters can save themselves and those around them, they will NOT be always around to save most of the OoH. If the order gets too militant against hell, I can see this happening.

  3. Demons are not the only agents of the infernal. And you do not even need a demon or infernal agent to get in mortal sin status most of the time. Pride is a capital sin, for example. *door to heaven closes to the OoH.

  4. God might get pissed off at the ooH as well. After all, demons are his agents as well, even if indirectly. They are the counter to the good, the darkness that makes His light shine. A demon-free land gets you WORSE christians, and that might not be what the Big One (or his public servants) desire to see.

  5. What you say can be done, but it takes quite some resources to implement. Not everybody will want to have such resources spent that way. After all we will not be the target for demon activity, will not? :wink:


I actually recall an old Peripherial Code ruling to the effect that demons are not enemies of the Order because the Order has no desire to declare war on Hell.

My version of this effect was a bit grander - say, a bell that tolls the hours of the covenant, and hit's everyone who hears it with DEO. :slight_smile:

But - the downside is it leaves you open to several counters. Demons can, say, afflict a visitor with pain and fear when they should be hit by DEO, and cause the wizards to leap to a false conclusion. Or, if they can manage it, killing them. So the magi think they have slain a demon (which has oddly left a corpse behind, hmmm... and sowing confusion and fear amongst both them and the rest of their visitors whose friend they have just slain with magic as far as anyone can tell.

On casting the spell on everyone you meet - that would take a long time! And unless you can reliably cast it silently and without gestures, you'll be casting a spell on everyone you meet - even a gently gifted magus is going to get a poor reaction from that, and anyone without that virtue is going to have serious problems. Plus, it's vulnerable to demonic manipulation as above - what do you do when you cast the spell on a passing priest and he drops dead on the spot, leaving his companion to work out why you murdered a pious churchman with your magic? Or a farmer asking for the price of the cow you just cursed to death, which would be the mildest response possible!

And finally, on the Code of Hermes - I can easily believe a suit being brought against you for accusing another maga of being a demon. If you didn't think she was a demon, why cast the spell on her? Do you routinely check every visitor for faerie or divine power, too?

Even if the Tribunal doesn't side with them (and they might), Wizard's War isn't an unlikely response to you continually implying that someone might be a demon...

So - it's an interesting way to work around the problem, but I think there are answers to it - and best of all, the answers generate story!

Can but not necessarially will. After all, demons do want you to sell your soul to hell. So, if a demon is [strike]over[/strike]confident and wants to tempt you into some sort of pact, it might not hide its nature. On the other hand, many demons are cowards.

Yes, this is perfectly viable.

The covenant's Aegis should keep out minor demons anyway. And those that sneak in by possessing somebody will be affected by the Aegis if they try to use powers etc within the covenant.

Unfortunately, there are still problems with slinging DEO spells at all and sundry on the off chance that the target is a demon.

When you cast a spell at a target that target has no idea what your intentions are (unless they've been using InMe to read your mind, in which case you have bigger problems!).

If you cast at another Hermetic magus all he is going to see (at best) is that a stranger is in the process of launching a PeVi attack against him. That is exactly the sort of action for which you will recieve in return a Fast Cast Pilum of Flame (or much worse). Will most magi (who are capable of replying) wait to see whether your PeVi attack is a DEO or something that destroy's their Parma Magica?

Magic critters, faeries, etc will also, if they recognise that you are casting a spell at them, consider this at best rude, at worst an attack (esp. if they recognise that it is a PeVi effect). Even mundanes who you mistakenly target with this will be offended, afterall if a mundane sees you casting spells at him then the social effects of the Gift will have him interpret your actions in the worst possible light.

So, while PeVi is a viable way to detect demons, it can create problems for you depending on the context.

It also isn't fool-proof anyway. If the demon is big enough to survive the first strike, and recognises what you are doing, it might create an undetectable illusion that it was unaffected.

And how do you propose to enforce this against immaterial beings?
Or for that matter, against a being that can turn (perfectly) invisible and create a (undetectable) illusion of itself to boldly march through your doorway?
I'm sure you can come up with other relevant scenarios to render this doorway irrelevant.
Aegis is generally a much better protection against demons.

Sensory magic is a neat trick - if you can get it.
For the rest of us, how do you propose to cast spells on that which you cannot sense?
Or are you garanteed to be a master of Second Sight?

And both of those are for the demon that bothers to operate directly - which is usually the ones you should worry about the least.

Mind you, the idea of using PeVi to identify demons is not exactly new - I know I saw it back in the 3rd edition as well.

Possession. For those times when the whole world seems to be against you.

Good stuff! I am glad because I felt rather unhappy about my own idea.

Wait. I'd never let this work in my game. To affect something with magic you have to first be aware of it. You have to somehow sense it. If a magus doesn't know if there is a demon there, he can't affect it with a destruction spell.


Matt Ryan


but he is aware of the person trespassing! And though I would allow it. I also would allow someone to cast an MuTe spell on a person, the spell just won't work.
Have you never heard about the apprentice who tried to influence a cat with ReMe? Or the priest performing an exorcism on an insane person (which was not possessed by a demon)?


Since might strippers specifically target the spiritual essence of an otherworld being, it might be reasonable to require that the caster sense that spiritual essence or at least be aware of it. I don't think we'd be losing much by eliminating area effect PeVi.

I play it exactly the same way as Matt. If you don't know that there is something to target (or know that there isn't anything to target), then the spell cannot be cast -- you simply don't have the correct parameters for casting. So under my paradigm, you can't use PeTe on a (naked) man, and you can't use PeVi on something that you don't know to be a demon. I don't expect everyone to run it like that, but we do.


So... presumably this ["must sense target" solution] does not extend to Intellego spells? So you could cast e.g. InVi to sense an active magic on an item/person? And only then can you target it with ReVi or whatnot.

Also, it clearly won't discourage Sensory Magic from operating just fine, or more simply area-based effects. What about enchanting a "room", being the inner-part of an elaborate gate that serves as the entry to the castle/covenant?

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If casting a PeCo "Wound" spell at Room Target (and let's throw in arcane connection range for the ride), you don't sense the targets, only the Target. The room could be crowded, or it will be desert, but if there is a valid target inside, it will be affected, despite you not knowing and being unable to sense it.
Or do you require spells with T: Boundary to need you to sense everything in the boundary?

Almost correct: I can cast a spell with T: Room (or Structure or Boundary) and affect a legitimate target that I was not aware of within the target Room (or Structure or Boundary).

Exemplia Gratia Primus: I cast Wnd of Mundane Silence (level 40) on the room I'm looking into - the invisible grog (under the Veil of Invisibility) becomes visible.
Exemplia Gratia Secundus: Instead, I cast a T: Room CrIg spell - the whole room will be covered in flames - the grog is injured.

I assume we all agreed on these?

Exemplia Gratia Tertius: I cast a T: Room version of The Wound that Weeps - every legal target (without resistance) is wounded including the invisible grog!

But this leads us to:
Exemplia Gratia Quatrus: Stephan of Veditus is scared of demons, but does not posses Second Sight, so he has a problem spotting them.
To deal with this, he invents a spell (The Hellish Minion Cast from this Room), which is a R: Touch, T: Room version of DEO. The resulting spell is level 10, the equivalent of a level 5 DEO spell with slightly modified parameters.
The next time Stephan feel paranoid about being watched by an unseen demon, in his lab, he casts this spell a few times.
Now, assuming he penetrates, this will remove 5 points of Might score from the demon per casting.

There's also another, sure fire way to identify demons.

Have a relic. Even a minor one.

An invisible demon might be targeted by a DEO room, and quickly get out without you noticing anything.

Relics, OTOH, will have a very visible and very destructive effects on demons.

Perhaps the insubstantial nature of Vim makes an exception, at least when directly targeting that Vim itself. Or perhaps it's something unique to demons. In the same way that Hermetic Magic can't use Intellego to detect demonic Vim, it might not be able to use Perdo to destroy that Vim. Just a thought.

Intellego always works differently with respect to sensory targets. I like your example though, especially if I turn it around. If I can't InVi a demon, why should I be able to PeVi it?

Sensory Magic breaks lots of normal rules.

I turn on the sprinkler system -> everythng in the room gets wet. Even the couple hiding behind the desk, despite me not knowing about them.

It comes down to ow we each read the definition of T: Room

By the same token, I turn on the burglar (demon) alarm for the room and you'd expect it to go off for every demon present. Yet it doesn't. Why not?

Perhaps Vim isn't really present in the room in a material sense the way Corpus would be. Or perhaps Hermetic Magic just isn't very good with demons.

No, this is totally wrong.

It is true that to target something you have to be aware of it, yes. (Unless it is an intellego effect to find it). You do have to sense that the target is there, but you don't need to know what the target is.

So, of course you can fire a PeVi DEO spell at anything you can see. You don't have to know that it is a demon. You just have to know that it is there. If the spell is DEO, it won't work if it the target isn't a demon --- but you don't need to know that before casting.

The OP also suggested a door way that nuked things crossing the threshold. So, yes, that device in particular either needs to detect things crossing it (which wouldn't always work with demons). Or, the device merely needs to be a constant effect, targeting the Room (which is valid as the target, the Room can be sensed). Alternatively, the device might be triggered by somebody stepping on it. So, it doesn't need to detect the demon. The demon triggers the device himself when he crosses the threshold.