5e invisibility and Detect Magic

[Plaguescarred]

Unless the invisible creature is hidden, you will know it's there and invisible

 

[Flexor the Mighty!]

Unless the invisible creature is hidden, you will know it's there and invisible

That sentence makes my brain hurt.

It didn't come up much in my 5e game but I pretty much ignored the hiding rules.

 

[Gadget]

A simple way to adjudicate this, aside from the excellent analysis already provided, is to ask yourself the question: Do I want the first level Detect Magic to serve as a poor man's See Invisibility? Does this make sense? Is it balanced? For me the answer is fairly straightforward: No.

 

[Oofta]

Whether or not you know an invisible creature is there (and I would say they are not automatically detected unless they take the hide action, that's a tangent), the spell is clear.

You know there's something magic, you don't know what and since you can't see the aura you don't know the school. At least that's how I rule it.

 

[Ristamar]

...or a bullseye lantern as it still casts a shadow, see “The Shadow” series.

I don't believe Invisibility works like that in D&D, whether it's 5e or any other edition, barring DM fiat.

 

[Ristamar]

That sentence makes my brain hurt.

It didn't come up much in my 5e game but I pretty much ignored the hiding rules.

As goofy as it may sound in real world terms, it actually runs rather smoothly as a game mechanic. It's also much more enjoyable than playing "Guess The Square" every time you fight invisible foes without the means to reliably locate them or rolling additional percentile dice for a miss chance ("I hit! Oh, damn... no, I didn't").

 

[smbakeresq]

I don't believe Invisibility works like that in D&D, whether it's 5e or any other edition, barring DM fiat.

Sure it does. You are still there occupying a space, subject to all affects. If you sprayed flour or paint in that space it would stick to the side of you facing the spray. Light is the same way.

That’s why they make clear plastic minis to mark your position. You still get the advantage of being attacked with disadvantage.

 

[Ristamar]

Sure it does. You are still there occupying a space, subject to all affects. If you sprayed flour or paint in that space it would stick to the side of you facing the spray. Light is the same way.

That’s why the my make clear plastic minis to mark your position. You still get the advantage of being attacked with disadvantage.

So the ambient light wouldn't reveal a shadow, but a bullseye lantern would...?

I can't tell if I'm being trolled at this point, so I'm just gonna back away from this one.

 

[smbakeresq]

Unless the invisible creature is hidden, you will know it's there and invisible

Correct. That’s the balance to invisibility, they have to take an action to hide, which might fail, which keeps them from attacking all the time. It’s also what makes rogues good, they can bonus action hide.

 

[Pauper]

Sure it does. You are still there occupying a space, subject to all affects. If you sprayed flour or paint in that space it would stick to the side of you facing the spray. Light is the same way.

See, this just increases the dumb, IMO.

So you've got a handful of flour and you throw it in the air; if it sticks to an invisible creature, you can now see it where the flour hangs in the air?

So where does this come in: "Anything the target is wearing or carrying is invisible as long as it is on the target's person."

The invisible target is wearing the flour. It's clearly on the invisible target's person. So it should go invisible just like anything else. Otherwise, there's a weird disconnect where, if you can get something on an invisible person that doesn't count as being 'worn' or 'carried', then the spell just ignores it. That's just dumb.

I'm a bit more amenable to the idea of spreading flour on the floor and watching for footprints or other indication that an invisible creature is passing through the area, but that's not as easy as it sounds in the midst of a confused melee, plus unless the invisible creature is already in the area of the flour patch, it can just avoid moving there and prevent its precise location from being known.

In other words, a bag of flour is no substitute for Dust of Appearance.

Also, light doesn't 'stick' to an invisible thing -- otherwise that thing would appear black, not invisible. Something is invisible if it neither reflects, absorbs, or emits light. (Which leads to another interesting physics puzzle in D&D -- what happens when an invisible creature picks up a torch?)

On the other hand, a magical lantern that reveals invisible creatures by casting their shadows in visible light would be pretty cool, IMO.

--
Pauper