Arcane Sight: What Do I See?

[Allanimal]

Suppose you're a wizard who has just cast Arcane Sight. For completeness, it is the only spell you have prepared and no other spells or magic items are affecting you at the moment.

The SRD tells us:

This spell ... allows you to see magical auras within 120 feet of you. The effect is similar to that of a detect magic spell, but arcane sight does not require concentration and discerns aura location and power more quickly.

You know the location and power of all magical auras within your sight. An aura’s power depends on a spell’s functioning level or an item’s caster level, as noted in the description of the detect magic spell. If the items or creatures bearing the auras are in line of sight, you can make Spellcraft skill checks to determine the school of magic involved in each. (Make one check per aura; DC 15 + spell level, or 15 + one-half caster level for a nonspell effect.)...

...



OK, so you look at Fighty McFighterson and thanks to the brightly lit room, you can see his smiling face and the many pointy metal objects he carries. Thanks to the Arcane sight, you can see the Christmas Tree aura of all his magic items and well.

You watch as he grabs a potion, your spellcraft check reveals that it has an aura of Illusion. Fighty McFighterson drinks it, and suddenly he has a new aura. You assume it's Illusion, and sure enough your awesome Spellcraft ability tells it is so, after a moment of concentration.

Now, Arcane Sight does not replace normal vision, so I am assuming that you can see that he's just turned invisible.

Fighty McFighterson's cohort (Igor Cannonfodder) then raises a lead curtain between you and Fighty, blocking Arcane Sight, and your normal vision. Unbeknownst to you, Monkette Monksdottir, who is under the influence of an Invisibility spell and carries a stone that is the object of a Silence spell, walks up to Fighty, hands him the stone, and takes his place. Fighty, (now also silent) saunters off to the other room, where he begins to raid the buffet table.

Now it just so happens that Monkette and Fighty, being twins, are the same height and weight, and for the purposes of this experiment, she is wearing & carrying exact duplicates of all of Fighty's equipment.

Now that Monkette and Fighty have traded places, Igor drops the curtain.
You can't see Monkette - she's invisible. But you can detect the aura of Illison all over her.

My question: Can you see that it is a different person? Do you get enough detail with Arcane Sight or detect magic) to recognize an invisible person? Recognize an invisible creature's race? Do you see a roughly humanoid-shaped glow or a detailed image showing all facial features, etc.

Bonus Question: Standing 180 feet away is 12th level Klerik von Göttservant, who casts Invisibilty Purge. There is a 60' radius invisibility-robbing divine goodness surrounding Klerik. This area and your Arcane Sight's range are not yet intersecting. But now Klerik takes a 5' step towards you. Does your Arcane Sight see this intersection of the two spell's area, or do you have to wait until Klerik himself is inside the 120' range of your Arcane Sight?


TL;DR: How much detail does Arcane Sight provide, and does a spell's "aura" extend to the full area the spell effects?

[evil-frosty]

I would say that you would not be able to tell that it is a different person as the only thing you are seeing are the magical auras which are the same. And I believe that the aura would spread throughout the whole area of effect.

[Greyfeld85]

As long as they're invisible (and you can't see through invisibility), and everything is exactly the same, and you have no reason to believe there's been a switch, then your character should believe it's the same character.

That said, any interaction that would reveal the character in question would have to accompany a bluff and/or disguise check to fool your character into believing that it's the same person (with any appropriate modifiers).

[Slipperychicken]

I like to think that each aura appears as a color-coded transparent mist emanating from the object/person. Conjuration's blue, Divination's green, Enchantment's pink, Evocation's slightly-less pink (or red), Illusion's purple, Necromancy's black, Transmutation's brownish-pink, Universal's probably white. The difference in color is probably subtle, so that's why you need Spellcraft to tell them apart.

When Fighter is walking around invisibly with a bunch of auras, you only know that those auras are in that square. You could reasonably deduce from the concentration that a creature was there, but would still suffer miss chance because you don't know of auras exactly where the body parts are -just some auras. If you heard footsteps too, it would become pretty obvious a creature was walking around.

You could probably guess the pattern of auras if you knew it well (if your buddy uses the same equipment all the time and you use Arcane Sight), but that's about it. You could try to make guesses based on the auras and their locations (transmutation aura in a belt pattern could be a Belt of Giant Strength. Amulet pattern could be Amulet of Health, etc).

[Allanimal]

OK, kind of what I thought.
What about this: If there was an invisible beholder (with its eye closed) and an invisible human in the room, could I tell which was which based only on the magical aura from the invisibility spell?

[Douglas]

OK, kind of what I thought.
What about this: If there was an invisible beholder (with its eye closed) and an invisible human in the room, could I tell which was which based only on the magical aura from the invisibility spell?
No, you could not. You would know which 5' square each one was in, that each aura is an illusion, and that each one is either a spell of 3rd level or lower or a magic item with caster level 5 or lower. That is the sum total of information the spell would give you.

If you concentrate on one or another of them, you might (it's unclear if this is possible against invisible creatures) be able to assess the spellcasting ability of each. In that case, the beholder would come up as not a caster (all their abilities are actually Supernatural, which Arcane Sight does not detect), and the result from the human would depend on his class levels. Unless the human is a spellcaster even this would not help you distinguish between them.

[Urpriest]

No, you could not. You would know which 5' square each one was in, that each aura is an illusion, and that each one is either a spell of 3rd level or lower or a magic item with caster level 5 or lower. That is the sum total of information the spell would give you.

If you concentrate on one or another of them, you might (it's unclear if this is possible against invisible creatures) be able to assess the spellcasting ability of each. In that case, the beholder would come up as not a caster (all their abilities are actually Supernatural, which Arcane Sight does not detect), and the result from the human would depend on his class levels. Unless the human is a spellcaster even this would not help you distinguish between them.

But the beholder is a different size, and thus takes up a different number of 5' squares. Should that matter?

[Greyfeld85]

The problem, as I see it, is that the term "aura" isn't really defined that well. What do they look like? Do they take specific shapes? Do they form themselves exactly around the object they're effecting? Do they have any sort of color or other defining characteristics? Can they increase or decrease in size? Are auras different depending on who casts the spell?

WOTC never goes into the specifics of exactly how auras are characterized. In the end, a lot of these sorts of questions are going to fall under DM Fiat. Whether you think that's good or bad is another matter entirely.

[Allanimal]

The problem, as I see it, is that the term "aura" isn't really defined that well.

That was I thought, but I wanted to be sure I didn't miss it somewhere. Sounds like that's the case, and as DM, anything more than the things specifically spelled out, it is up to me to decide how much is revealed and in what detail.

[Kelb_Panthera]

You got it. Though in the beholder example you could tell it's not the same invisible thing. Auras should almost certainly take at least the same space as the effect that produces them. The invisibility on the beholder is taking up four 5ft squares, while the invisibility on a human is only taking up one.

[Douglas]

Yes, I overlooked the size thing; you should at least be able to tell how much area (to the nearest 5' square) an aura occupies, which would distinguish between size categories Large and higher. This would not let you distinguish between a beholder and an ogre, however, as they are both large size.

[Elric VIII]

I believe we are considering this from a perspective too close to our own mundane one. The existence of the Spellcraft skill and its ability to determine auras implicitly establishes the fact that there is a way to differentiate the aura of different spells. We, however, cannot perceive spells (since they do not exist in our reality), so we have no common basis for relation of the game to real life.

Now, from determining the specific spell in question you can infer things about the target. Such as if you detect an invisible creature that is under the effects of Polymorph (http://www.d20srd.org/srd/spells/polymorph.htm) you can conclude that the creature is a) living and b) either a spellcaster himself or in a position that makes him willing to be subjected to the spell.

*Speculation:* Now, assuming you believe that the above is true (while not explicitly stated anywhere, it is logical to assume these points), you can rework the question to be more specific and relevant. So, I think the new question would be "[B]based on my knowledge of the spells, items, and auras affecting the target, can I determine any identifying features?"

From that point it follows with the stipulation in the DMG that anything not mentioned as operating otherwise functions as it does in the real world. Namely, you can tell the difference between two people by observing differences in form, appearance, manerisms, etc without them telling you who they are (think about identifying two of your friends when their backs are turned to you).


The main point behind this jumble of words is that the answer to the question is not explicitly stated anywhere, but there is justification for allowing your character to engage in exercises of perception or logic in order to determine identity.

[nyjastul69]

...The invisibility on the beholder is taking up four 5ft squares...

*nitpick* A beholder occupies 8 'squares' of space. They're actually cubes. Creatures are as tall as they are wide. It could matter in regards to LoS.

Edit: I mention this because LoS is relevant to the OP's question. I wasn't trying to pick nits. Also, nothing in Arcane Sight or Detect Magic change normal sight. Normal sight should function, and be considered, when describing magical auras.