This is to house rule issues I originally brought up in the Detect Magic & Magic Traps / Invisibility thread, plus other issues dealing with perpetual casting of Detect Magic spoiling the use of long lasting figments, such as Illusionary Wall and Permanent Illusion.
Basically, my issue with Detect Magic has much more to do with out-of-combat uses, than the in-combat ones. The spell reveals too many secrets for a cantrip that can be cast at will, by any full spellcaster. Spelltraps, magic device traps, magic items, invisible creatures, and figments are all exposed. These are all things that DMs will often wish to keep secret.
So I have brushed the dust off of my +5 bat of Holy Homebrew Gimping, and smite the cantrip thusly:
Plain Sight rules for the Detect Magic cantrip
- Contrary to the spell description, Detect Magic does not penetrate barriers, and even ordinary clothing can hide the auras of magic items.
- the auras of Illusion spells are hidden from Detect Magic, unless the Illusion has been successfully disbelieved by the Detect Magic-er.
- If a Per check is required to notice a magic item (including magic device traps), spell or sensor, then the associated aura is hidden from Detect Magic, unless the Per check is made. You get a non-cumulative +20 on this check if one or more persons points you to the relevent item, spell or sensor. Pointing is a free action.
-Area affecting spells (e.g. Alarm) are considered to be in plain sight whenever the Detect Magic-er can view the area that the spell affects.
-auras that are not in plain sight are hidden from Detect Magic, and are not detected in any way, shape or form, regardless of number of rounds of concentration.
Please comment on whether you like or dislike the rules, or post any questions you might have, or if you know of any completely ridiculous implications which would stem from sensibly applying these rules.
Edit: These rules are an extension of house rules I used for 3.5. The idea is that Detect Magic only detects the auras of things which you already see. For Pathfinder, I have extended the rules to cover Illusions in general, where as my 3.5 rules were mainly for invisible creatures and magic traps.
Personally I dislike the idea of only being able to detect on things you can see. I imagine it almost being like a "force-sense" where you just get a sense that there is magic "in the air" in an area. That's why I posted my idea for detect magic being a 1st level spell with 24 hour duration spell that senses all around you for 30' passively at all times. That way you're not casting it over and over, it works when you're not thinking about it, and its not automatic (you have to make concentration checks to notice magic auras entering your field of detection).
I'd either do that, or stick with just leaving all cantrips as they were in 3.5.
But hey, its your campaign, so do as thou wilt :)
I don't want to change how cantrips at will works over a single, overpowered cantrip.
I have no objection to your idea of making it a 1st level spell, I just don't get how the checks are supposed to work.
jreyst wrote (in other thread):
Concentration Check:
1d20+level+(ability modifier) for free
1d20+level+(ability modifier x2) as a standard actionFree Check (assuming 3,4,5,6 ability mods)
1 1d20+1+3= 5-24
5 1d20+5+4= 10-29
10 1d20+10+5= 16-35
20 1d20+20+6= 27-46Standard Check Range (assuming 3,4,5,6 ability mods)
1 1d20+1+6= 8-27
5 1d20+5+8= 14-33
10 1d20+10+10= 21-40
20 1d20+20+12= 33-52
If you could elaborate on this part, it would help me. Also if you want to repost your idea here, that would be good. More alternatives is a good thing.
I don't like houseruling it. My suggestion (that I posted on the other thread) is that a smart dungeon crafter will litter the place with continual flame.
Sure, if you detect something and figure out it's not Evocation (which takes even more time), it might be a trap or something. You can always place a few Alarms around (cheaper than something more elaborate) to also 'jam up the radar.'
Here was my original idea about Detect Magic. Mind you I typed it up quickly the first time and suggested the DC's might need to be modified but here is the idea again...
First what I originally wrote...
Detect Magic
School: divination; Level bard 1, cleric 1, druid 1, sorcerer/wizard 1
Casting Time: 10 minutes
Component: V, S
Area: 30' radius emanation from you
Duration: 24 hours
Effect: You make an automatic (free) concentration check anytime a magic item, ongoing spell, or spell-like-effect, enters the area of effect. The first check is automatic and requires no action. Intentional checks are made as standard actions. When intentionally focusing and searching for effects you add your relevant ability bonus to the concentration check instead of once.
Concentration Check:
1d20+level+(ability modifier) for free
1d20+level+(ability modifier x2) as a standard action
Free Check (assuming 3,4,5,6 ability mods)
1 1d20+1+3= 5-24
5 1d20+5+4= 10-29
10 1d20+10+5= 16-35
20 1d20+20+6= 27-46
Standard Check Range (assuming 3,4,5,6 ability mods)
1 1d20+1+6= 8-27
5 1d20+5+8= 14-33
10 1d20+10+10= 21-40
20 1d20+20+12= 33-52
The DC to detect a spell or item depends on its aura strength:
Aura Strength, DC
Faint, 20
Moderate, 15
Strong, 10
Overwhelming, 5
Each time you successfully detect an aura you gain additional information.
Detection #, Information
1, Presence or absence of magical auras.
2, Number of different magical auras.
3, Power of the most potent aura.
4, Strength and location of each aura.
5+, If the items or creatures bearing the auras are in line of sight, you can make Knowledge (arcana if arcane magic, or religion if divine) skill checks to determine the school of magic involved in each. (Make one check per aura: DC 15 + spell level, or 15 + 1/2 caster level for a nonspell effect.) If the aura emanates from a magic item, you can attempt to identify its properties (see Spellcraft).
Note: Magical areas, multiple types of magic, or strong local magical emanations may distort or conceal weaker auras. Modifiers to the DC's may apply at DM discretion.
Magic Traps: Spells that function as magical traps have less than a faint aura, and the DC to detect a magic trap is 30+the spell level of the spells in place on the trap.
Then a summary and explanation..
So its a 1st level spell that the character casts first thing in the morning. It takes 10 minutes to cast (making it sort of a daily ritual type effect). Then it lasts all day, until the next morning. It functions in a 30' radius around the caster and gives him a free chance to detect any magic auras that come within his 30' area of effect. He does not need to be aware of them or see them... its sort of a "sense the force" effect. The DM makes this roll without the players knowledge. If the roll is successful the character simply notices "there is magic". Mind you the character would probably be accustomed to the normal amount of magic that emanates from his party members so it would only trigger on new auras that appear or enter the area. So anyway, then, if he made the roll his "spider sense" goes off. The player can then stop and spend standard actions to try to focus in on the source of the effect. When he does, his chance gets better, as he is taking time to try to pay closer attention.
I only included this section...
Free Check (assuming 3,4,5,6 ability mods)
1 1d20+1+3= 5-24
5 1d20+5+4= 10-29
10 1d20+10+5= 16-35
20 1d20+20+6= 27-46
Standard Check Range (assuming 3,4,5,6 ability mods)
1 1d20+1+6= 8-27
5 1d20+5+8= 14-33
10 1d20+10+10= 21-40
20 1d20+20+12= 33-52
As a sort of worksheet so I could see what the range of possible rolls would be for the free/passive check and the standard action/intentional check.
So anyway....
Then, each time the character succeeds a check he goes up one level in detail, as shown here...
Detection #, Information
1, Presence or absence of magical auras.
2, Number of different magical auras.
3, Power of the most potent aura.
4, Strength and location of each aura.
5+, If the items or creatures bearing the auras are in line of sight, you can make Knowledge (arcana if arcane magic, or religion if divine) skill checks to determine the school of magic involved in each. (Make one check per aura: DC 15 + spell level, or 15 + 1/2 caster level for a nonspell effect.) If the aura emanates from a magic item, you can attempt to identify its properties (see Spellcraft).
That just says that the first time he succeeds he just knows "something is there" and each time he succeeds from there on he gains additional information. After the 5th success he gets the most detail.
I decided to make the checks Concentration checks instead of Perception checks because I didn't want to have to scale the DC's to accommodate PC's who max out Perception, not to mention I figured its more a sense of a characters connection to magic than there normal "perception" at play.
So an example...
Dave the Mage walks into a room. He has Detect Magic active. In the room is a magic item on the floor. The DM makes a free roll for Dave. This roll is a concentration check (1d20+level+(ability modifier)). The DC is dependent on the aura strength. If it was a faint aura the DC is 20. If its overwhelming the DC is 5. The DM rolls and the check fails. the item on the floor has a faint aura and Dave is just a noob. So Dave enters the room and walks around for 5 rounds while Twinkletoes the rogue looks for traps and secret doors. During each of those 5 rounds the DM continues making free passive checks for Dave, without Daves player's knowledge. On round 3 he succeeds. Something sparks in his head. The DM tells Daves player that "while waiting for twinkletoes to finish frisking the wall you detect magic in the area... you are not sure where or what it is, but you have a feeling something is out there." Dave instantly tells Twinkletoes, "Dude back up and stop touching the wall, my magic sense just went off" Meanwhile Twinkletoes steps back and says "sounds good."
Dave starts spending standard actions to try to focus on the magic source. In the first round he succeeds on his check and determines there is one aura he is not accustomed to in the area... but he is not sure where yet..." He continues focusing. In the next round he fails his check but tells Twinkletoes, "hold on... still scanning..." then in the next round he makes his check and determines that the aura is faint. He tells Twinkletoes, "its something weak... hold on..." and continues scanning. The next round he makes his check again and now knows that its one aura, faint, and its in the corner of the room. He points to the corner and says "in the corner... from the chest..."
Twinkletoes tiptoes over to the corner and examines the chest carefully.
Because the source of the aura is not in line of sight (it is in a chest) Dave can not gain further information.
Now Twinkletoes must do his job and work with the chest. The thief is still important and the mage gets information, but not all the goods.
Note that if it were a magic trap the DC would be a base of 30+spell level of the magic in place. The range of possible roll results was shown on the table (here it is again). The number at left is the level of the character. The number after the = sign is the range of possible results. This shows that a level 1 character could not possibly detect even a level 1 magic trap (probably need to rejigger the numbers).
Standard Check Range (assuming 3,4,5,6 ability mods)
1 1d20+1+6= 8-27
5 1d20+5+8= 14-33
10 1d20+10+10= 21-40
20 1d20+20+12= 33-52
A level 20 character would roll from 33 to 52 on his check, automatically detecting a level 1-3 magic trap, but having a chance to fail harder traps (though not likely).
Ok that's all I have time to type atm lol
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I would have ruled that detect magic doesn't reveal Illusions as such.
My understanding of the illusion of a wall (or anything really) even though a magical effect, affects the mind of the observer such that they are fooled in believing it is real.
Therefore it wouldn't matter if they are using their eyes or the results of a spell, if they do not have reason to suspect it is fake or do not attempt to disbelieve by interacting with the illusion, then Detect magic should not reveal it. The spell hasn't failed, its just that the Illusion is more powerful and is masking the result.
Firing off a Detect Magic in the direction of a piece of architecture every 6 seconds would tend to exhaust you as well. I would have thought it would be like focusing every 6 seconds on every single item around you - eventually the word migraine comes to mind.
YMMV ofcourse
@jreyst
From what you have posted, It looks to me like detecting magic traps would be difficult, but it would still work as an effective Illusion buster. This could be a DM preference issue, I am opposed to common, low level magic spoiling higher level spells. But I know that there are other examples of lower level beats higher level - Protection from Evil can prevent a lot of bad stuff, and I have no intention of house ruling it.
I would have ruled that detect magic doesn't reveal Illusions as such.
My understanding of the illusion of a wall (or anything really) even though a magical effect, affects the mind of the observer such that they are fooled in believing it is real.
Figments aren't mind affecting. I would otherwise agree with you, that it is reasonable that a mind affecting Illusion would affect the Detect Magic-er.
Firing off a Detect Magic in the direction of a piece of architecture every 6 seconds would tend to exhaust you as well. I would have thought it would be like focusing every 6 seconds on every single item around you - eventually the word migraine comes to mind.
YMMV ofcourse
This would require some sort of house rule, although it is a reasonable premise for making a house rule. My idea is that since Detect Magic is the bad actor (as I see it), the house rule should be for Detect Magic.
@jreyst
From what you have posted, It looks to me like detecting magic traps would be difficult, but it would still work as an effective Illusion buster. This could be a DM preference issue, I am opposed to common, low level magic spoiling higher level spells.
I agree. You could simply say though that an illusion is treated as a magic trap, ie, its base detection DC starts at 30 then you add on spell level. High level casters would detect low level illusions easily but still possibly fail to detect high level illusions.
Dilvish: Are you contemplating a response to various counterpoints? You have yet to address some of the ways to make it not a problem.
I think by starting a new thread he was basically saying "I've read all your ideas about why its not a problem and still feel it is a problem. Thank you for your input but now I'd like to get input from any who agree it is a problem. If you feel it is not a problem, thank you for your information thus far but I don't need any more information from you at this time."
Forgive me if that is an inaccurate understanding of the status at this time. I do not mean to put words into anyones mouth so if that's not true then just ignore me :)
@ William Timmins
You mean cluttering up a dungeon with 'red herring' spells?
1- I don't think that I would do it. It is a smaller overall change to gimp the cantrip, than to do that.
2- The line about stronger, multiple auras obscuring Detect Magic, has no mechanics to give it bite. Someone would have to make them up.
The thread is about alternatives, if you come up with a workable system to keep Detect Magic from spoiling secrets, feel free to post it. It should have some more details about what the results of Detecting Magic in an area full of red herrings would be like.
You mean cluttering up a dungeon with 'red herring' spells?
1- I don't think that I would do it. It is a smaller overall change to gimp the cantrip, than to do that.
For me personally, doing that (laying a ton of fake or "red herring" traps or spells around) is silly and doesn't seem reasonable... for a non-high magic campaign. As always, if you like that sort of thing, go to town.
2- The line about stronger, multiple auras obscuring Detect Magic, has no mechanics to give it bite. Someone would have to make them up.
Agreed.
The thread is about alternatives, if you come up with a workable system to keep Detect Magic from spoiling secrets, feel free to post it. It should have some more details about what the results of Detecting Magic in an area full of red herrings would be like.
Agreed.
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We've run into this in a couple of my games too, and I have one other possible solution.
Limit the range to touch - this makes spells such as arcane sight seem like much better upgrades worth the increase in level. This leaves the utility of using detect items on loot there - the mage might have to get her hands a little dirty as they search for magical treasure, but that's what prestidigitation is for anyway! Using this change alone removes the inadvertent revelation of illusions as such - unless the caster thinks it's an illusion and runs her hands over it, she'll be unable to detect its illusion aura. It prevents it from being used to find invisible people unless they're right up next to you. And while it still retains a lot of utility, it makes sense to me that low level spells would expose you to more risk as you seek to uncover the magical nature of things, because you have to actually touch them.
jreyst: A non-high magic campaign won't have very many magic traps to begin with, would it? And magic mouth is a 2nd level spell costing 10 gp.
If I've spent 500 gp making a burning hands trap (CR 2), I'm not going to spend 50 gp putting a few magic mouths in the area?
I'm not saying you can't run things as you want, but the objection doesn't seem to fit the way the game functions, so I'm wondering if we're on the same page.
'Using the tools available and reasonable within the system' seems a smaller change to me than changing the system.
@ Jess Door
And I was worried that maybe I was being to severe, with my gimping. (Although I wasn't very worried).
However, limiting it to touch range does accomplish everything that I see as being needed and it is very simple. And in a magical world, it is hard to see even a touch range Detect Magic as being less powerful than the other cantrips.
@ William Timmins
Who is changing the system here. The thread is about de-powering a single cantrip, that is overpowered - especially if it can be cast at will.
Plus, in your examples, why wouldn't a Detect Magic-er simply detect all of the auras?
The Definition of the word Detect is "to discover or determine the existence, presence, or fact of" by this, the spell "Detect Magic" should only allow for the casters to determine the presence of magical auras. Perhaps simply changing the effect of the spell to include only what occurs in the first round of concentration, which is "1st Round: Presence or absence of magical auras", and perhaps making the spell a 30 ft. emanation from the caster. Still pretty good for a cantrip In my opinion.
So, say a player is searching for someone in a room who he/she knows has just cast the invisibility spell upon themself. The player may cast the spell Detect Magic to discern if that person (along with any additional magic auras that may be within 30 ft.) is within the area of the spell (which is now a 30 ft. emanation.)
Granted, the spell would be useless if there were more than the one aura in the radius, but then again...it is a cantrip.
Detect Magic would detect all of the auras, sure. But that means all you know is 'this room is filled with a bunch of magic auras, same as the last 10 rooms,' not 'oh no! THIS room has a magic something in it!'
It cuts down on useful information unless you take time to examine each and every magic aura (at which point all you know is school, which may not be useful), and then have the rogue check each and every one.
Combine with mechanical traps, a few magic traps covered with magic aura ('not magic'), and you cut detect magic down from the problem you noted to 'a source of somewhat useful information at the cost of slowing your progress considerably.' Which seems about fair.
Personally I dislike the idea of only being able to detect on things you can see. I imagine it almost being like a "force-sense" where you just get a sense that there is magic "in the air" in an area. That's why I posted my idea for detect magic being a 1st level spell with 24 hour duration spell that senses all around you for 30' passively at all times. That way you're not casting it over and over, it works when you're not thinking about it, and its not automatic (you have to make concentration checks to notice magic auras entering your field of detection).
I'd either do that, or stick with just leaving all cantrips as they were in 3.5.
But hey, its your campaign, so do as thou wilt :)
I like this. I think I might use this in my next campaign.
It cuts down on useful information unless you take time to examine each and every magic aura (at which point all you know is school, which may not be useful), and then have the rogue check each and every one.
With Detect Magic, you don't have to focus on each one seperately. You gain the information about all the auras you detect simultaneously.
Although, having a rogue check each and every one would be time consuming.
Hrm.
'If the items or creatures bearing the auras are in line of sight, you can make Knowledge (arcana) skill checks to determine the school of magic involved in each.'
I had read 'you can' to suggest you had to take an action to examine each one, but it doesn't specifically say that. So, fair enough!
Plus, rogue has to check each aura, plus make sure there isn't a mechanical trap right in front of it, or whatnot.
Hrm.
'If the items or creatures bearing the auras are in line of sight, you can make Knowledge (arcana) skill checks to determine the school of magic involved in each.'I had read 'you can' to suggest you had to take an action to examine each one, but it doesn't specifically say that. So, fair enough!
Plus, rogue has to check each aura, plus make sure there isn't a mechanical trap right in front of it, or whatnot.
Don't forget that detect magic goes off any anything magic in the area, including the magics auras and items that are present on the other players. This alone can greatly decrease its usefulness.
Either the caster has to go in front all the time(and risk stepping into non-magic traps or encounters) or the spell becomes next to useless because the caster will always detect magic.
The effect is blocked by a foot of stone or a thin sheet of lead. Imagine placing a magic trap in a narrow stone crevasse. From the direction of approach, detect magic would be blocked by over a foot of stone until you were right on top of the trap at which point the trap goes off.
Also, you can use detect magic as the trigger for a magic trap. If you can detect it, it can detect you, and detect magic is a magic spell and puts a magic aura on the player.... BOOM!
This is the 'lets gimp it' thread, the apologizing for it thread is here Detect Magic and Magic Traps / Invisibility
I don't want to come off as being snarky, but this thread is intended mainly for people already convinced it is in need of gimping.
I personally just make the caster actually concentrate on the spell to get any info out of it. If you are walking down the hall, you aren't concentrating on your detect magic spell, so you won't notice that tapestry is an illusion covering a secret passage. And I'm pretty sure that if the wizard even tried walking 30 ft, stopping for a full round to concentrate, then walking again, the rest of the party would kill him.
I personally just make the caster actually concentrate on the spell to get any info out of it. If you are walking down the hall, you aren't concentrating on your detect magic spell, so you won't notice that tapestry is an illusion covering a secret passage. And I'm pretty sure that if the wizard even tried walking 30 ft, stopping for a full round to concentrate, then walking again, the rest of the party would kill him.
That is a house rule, as it is a standard action to concentrate. It just means that as they move at normal, 30ft/round movement that they only ever detect the presence of magic. They would need to stand still for 3 rounds to detect what specifically is magical, but when they turned the corner (and moved their cone that way) and saw the tapestry, they would know something is in the hallway is magical on round 1. He may already have that knowledge if someone is in front of him.
Dilvish: THANK YOU for this much-needed thread! As Jess Door mentioned, it drives me up the wall that, strictly as written, an at-will cantrip defeats all invisibility, illusions, and magical traps. We'll be using the line-of-sight limitation, and also the idea that illusions mask their own auras (but detecting magic on one counts as "interaction"). Also, magic traps' auras have a detect DC equal to the trap's, so you can detect it with the Perception skill as a rogue would, or with detect magic as a caster, but either way it's a difficult task.
Also, magic traps' auras have a detect DC equal to the trap's, so you can detect it with the Perception skill as a rogue would, or with detect magic as a caster, but either way it's a difficult task.
This is one thing that I've houseruled.
I haven't posted the rules that I intend to use for Magic Device traps, partly because no one has asked, but also because they are probably overly complex. This is because I treat certain trigger spells as being seperate entities from the actual traps, and cannot justify Detect Magic not detecting an area Alarm spell (it just seems to me like the sort of spell which Detect Magic ought to detect).
While I post them here, I also encourage DMs to come up with their own solutions, if these aren't suitable. And if you come up with something that is just plain better- meaning simpler and workable in most or all situations, please post it.
Triggers
A magical sensor trigger is hidden, unless the Detect Magic-er has made the DC 20 Per check to notice the sensor.
An area Alarm spell trigger is hidden only if the Detect Magic-er cannot view the area the spell affects.
A touch range trigger is hidden if the associated Per check to notice the the trap, has not been made by the Detect Magic-er.
The aura of visual (e.g. True Seeing) and detection triggers (e.g Detect Good) is likewise hidden if the associated Per check to notice the the trap, has not been made by the Detect Magic-er.
If Magic Aura is built into a trap, the aura of touch range triggers, visual and detection triggers is hidden from Detect Magic.
Magic Device traps
The aura of a Magic Device trap is hidden, unless a Detect Magic-er has made the necessary Per check to notice the trap.
The Magic Aura spell may be included as part of trap construction, in which case the aura of the Magic Device trap is always hidden.
I also want to throw out a few ideas inspired by posters in this thread and in the other one in the rules section. Mynamesjake suggested mechanically triggering Magical Device traps. I think this is workable without bending the rules much, by using an undead rodent attached to a push rod, that gets pushed into a touch triggered trap. It should probably be an area affect spell that is triggered, such as Cone of Cold or Lightning Bolt, since logically any targeted spell would target the rodent. It would probably be pointless to have the trap be self-resetting, since the rodent involved would be destroyed when the trap is triggered.
Or a DM could simply rule that mechanical triggers, in general, are ok for magic device traps.
And Charender, a few posts up in this thread, suggested Detect Magic as a trigger for a Magic Device trap. I like this idea, particularly since I can find no rules that say that a trap can't have more than one trigger. However, while I am thinking that the Detect Magic cone should not have it's own aura (i.e. only the Detect Magic-er has the associated aura), that could be wrong. It may be that the Detect Magic cone, does have it's own aura, and that would change the scenario under which the trap is triggered. The trap would be triggered if the two detection cones overlapped. It becomes unclear to me how the trap would actually target anything, in that case.
We've run into this in a couple of my games too, and I have one other possible solution.
Limit the range to touch - this makes spells such as arcane sight seem like much better upgrades worth the increase in level. This leaves the utility of using detect items on loot there - the mage might have to get her hands a little dirty as they search for magical treasure, but that's what prestidigitation is for anyway! Using this change alone removes the inadvertent revelation of illusions as such - unless the caster thinks it's an illusion and runs her hands over it, she'll be unable to detect its illusion aura. It prevents it from being used to find invisible people unless they're right up next to you. And while it still retains a lot of utility, it makes sense to me that low level spells would expose you to more risk as you seek to uncover the magical nature of things, because you have to actually touch them.
I agree on making the range limited to touch, as this is very appropriate for a cantrip learned by a novice wizard learning their craft. They can upgrade to more powerful spells as they level.
Limit the range to touch
This is wonderful. +1
Let's not go to Camelot; it's a silly place.
I'm also trying to solve this problem in my game — complicated by the presence of a Paladin and the fact that I want to keep the spells detect magic and detect evil roughly approximate. Note that detection thwarting invisibility is just as much a problem with Paladins.
I play via maptool, and I find that the process of detecting through walls (especially ceilings and floors) requires WAY too much thought during the session. It can't really be shifted into prep time, although I have considered creating a token on the hidden layer for each aura.
The conical area is also annoying, though not impossible, to display in maptool.
My current compromise is like a hybrid between two of the above suggestions: Detect magic is 30' LoS, not conical. It can penetrate barriers of the thicknesses mentioned in the spell, but only while the detecting player is touching the surface in question.
I would love a magic bullet solution for this one, but at the same time I don't mind 18 seconds of concentration thwarting invisibility magic. If someone takes three whole rounds in combat to find an invisible opponent, I'm apt to let them have it. The 50% miss chance still applies.
Curious to hear more ideas — the less invasive surgery on the wording of the spell, the better.
This kind of problem really makes me wish for a whole book on how magic works... the Pathfinder Grimoire. I dream of it still.