D&D (2024) Line of sight ruling

[Charlaquin]

It never does, does it.

No, indeed. The current designers at WotC seem allergic to making clear, direct statements of any kind.

 

[Lazybones]

Line of sight is defined on p.45 of the DMG; the wording there has nothing to do with whether the target can see and has more to do with the obstruction, if any, between two spaces. If they'd wanted the spell to be dependent on what the target can actually see/perceive, I think the spell would have stipulated that.

 

[Shiroiken]

This is where people forget the DMG. In Chapter 1, under Players Exploiting the Rules, it specifically calls out that the rules rely on Good Faith Interpretation. I'd say at least 90% of people's issues can be resolved by recalling that simple principle. In this particular case, if the fear source is hidden/invisible, then you obviously have no line of sight (per the Sage Advice), but you can't simple close your eyes to "make it go away." This is why we have a DM and not playing a CRPG.

 

[MerricB]

Line of sight is defined on p.45 of the DMG; the wording there has nothing to do with whether the target can see and has more to do with the obstruction, if any, between two spaces. If they'd wanted the spell to be dependent on what the target can actually see/perceive, I think the spell would have stipulated that.

Check the sage advice I quote in the first post; they explicitly say that is not the definition.

 

[James Gasik]

When Scooby and Shaggy run away after being frightened by a monster or ghost, they need to be in another room that does not have line of sight before they can eat a Scooby-Snack and make their save.

A scared 5-year-old thinking the coat on the back of the door is a monster is not going to fine if you say just close your eyes or place a blindfold on him. The child or the coat needs to be removed from the room, and line of sight.

A player of mine had a similar argument when they Frightened a monster that was unable to see them due to Invisibility. "I would think they'd be more terrified of not being able to see something they're Frightened of, not less". We've since instituted what I call the "Slasher Houserule", referring to horror movies featuring a psychotic, sometimes supernatural, killer who can appear out of nowhere. You may not know where to run, but you don't stop being terrified.

 

[Lazybones]

Check the sage advice I quote in the first post; they explicitly say that is not the definition.

I would not allow the options you suggested (closing your eyes or looking away) as solutions. I read "can't" as "unable to," not the temporary, player-initiated conditions you described. I agree with the sentiment of the poster above; if you know the thing that you're scared is standing behind you but you turn away or close your eyes, you're going to be more afraid, not less.

I guess I'll add it to my list of house rules, in case it comes up in my game.

 

[EzekielRaiden]

If the only sense involved is sight, then OK. But if the victim is hearing illusory screams and-or smelling illusory rot as well then being blinded might only serve to make the fear worse.

Per the 5e version of the spell, sight appears to be the only sense involved. Spell has a range of "self" (so the illusion is projected over your own body), and once any given target no longer has line of sight to you, they can start making saves to see if the effect expires (so it isn't instant, which is what I implied earlier, my apologies.)

To be fair, this is one way in which 5e differs from what I'm used to; in my case a Fear effect would have a set duration regardless of the relative subsequent positioning of the source and target, thus allowing the target to run around a corner or through a door and, still frightened, keep on running (or, if there's nowhere to run, cower in a corner) until the fear wears off on its own.

Well. The idea is that the fear won't go away until the spell's normal duration unless you can hide behind something.

Or casting any spell into darkness.

Assuming no darkvision, sure. Plenty of species in 5e have it (though not all!) and Warlocks can actually get super-ultra darkvision, which can see through both mundane and magical darkness (which no species provides).

Does it also say you need line of effect between the caster and the spell's point of origin, for targeted spells? Example: if I'm in my hous looking out the window and I see you skulking around in the garden can I drop a Hold Person on you? I seem to recall the RAW answer here would be "no I can't" but that's never made sense to me.

Well, here are the relevant rules. As noted, "line of effect" isn't a phrase the game uses. A few separate sections stitched together here for ease of comprehension. All emphasis in original.

---

A Clear Path to the Target​

To target something, you must have a clear path to it, so it can’t be behind total cover.​

​

If you place an area of effect at a point that you can’t see and an obstruction, such as a wall, is between you and that point, the point of origin comes into being on the near side of that obstruction.​

​

[...]​

Areas of Effect​

Spells such as burning hands and cone of cold cover an area, allowing them to affect multiple creatures at once.​

​

A spell’s description specifies its area of effect, which typically has one of five different shapes: cone, cube, cylinder, line, or sphere. Every area of effect has a point of origin, a location from which the spell’s energy erupts. The rules for each shape specify how you position its point of origin. Typically, a point of origin is a point in space, but some spells have an area whose origin is a creature or an object.​

​

A spell’s effect expands in straight lines from the point of origin. If no unblocked straight line extends from the point of origin to a location within the area of effect, that location isn’t included in the spell’s area. To block one of these imaginary lines, an obstruction must provide total cover.​

---

So if you are looking through a pane of transparent glass, then the answer is "no you can't". If you are looking through an open window, the answer is "yes you can". If, for example, there is a window already open, you could walk up to it, cast the spell, then use your one free "interact with an object" interaction to close the window and retreat. Other kinds of spells may or may not work that way, depending on the specifics of the spell in question.

 

[Peter BOSCO'S]

They could, however, command you to fall prone, which doesn't even take an action.

Clearly everyone falls prone face up or their neck twisted so that they can still see everything, otherwise prone would impose some sort of penalties on perception, which it does not.

 

[Lanefan]

Per the 5e version of the spell, sight appears to be the only sense involved. Spell has a range of "self" (so the illusion is projected over your own body), and once any given target no longer has line of sight to you, they can start making saves to see if the effect expires (so it isn't instant, which is what I implied earlier, my apologies.)

No worries.

Well, here are the relevant rules. As noted, "line of effect" isn't a phrase the game uses. A few separate sections stitched together here for ease of comprehension. All emphasis in original.

---

A Clear Path to the Target​

To target something, you must have a clear path to it, so it can’t be behind total cover.​

​

If you place an area of effect at a point that you can’t see and an obstruction, such as a wall, is between you and that point, the point of origin comes into being on the near side of that obstruction.​

This is, if there's only a window (or a Wall of Force) between me and the target I can see the target point.

Now with something like Fireball it's obvious the spell will wreck on the unseen obstruction as the little bead has to go from the caster to the origin point. And if the spell starts at the caster, such as Burning Hands, then again the invisible obstruction blocks it. But that's not true of all spells. Take Flaming Sphere, for instance. Or Light. Or Hold Person. I cast it here, sure, but the effect happens over there at a point or target I can see, and as nothing physical has to travel from me (the caster) to the spell's point of origin then casting it through a WoF or a closed transparent window should IMO work.

​

[...]​

Areas of Effect​

Spells such as burning hands and cone of cold cover an area, allowing them to affect multiple creatures at once.​

​

A spell’s description specifies its area of effect, which typically has one of five different shapes: cone, cube, cylinder, line, or sphere. Every area of effect has a point of origin, a location from which the spell’s energy erupts. The rules for each shape specify how you position its point of origin. Typically, a point of origin is a point in space, but some spells have an area whose origin is a creature or an object.​

​

A spell’s effect expands in straight lines from the point of origin. If no unblocked straight line extends from the point of origin to a location within the area of effect, that location isn’t included in the spell’s area. To block one of these imaginary lines, an obstruction must provide total cover.​

---

So if you are looking through a pane of transparent glass, then the answer is "no you can't". If you are looking through an open window, the answer is "yes you can". If, for example, there is a window already open, you could walk up to it, cast the spell, then use your one free "interact with an object" interaction to close the window and retreat. Other kinds of spells may or may not work that way, depending on the specifics of the spell in question.

It's unfortunate that the two spells they name there - Burning Hands and Cone of Cold - both originate from the caster; this doesn't help with spells whose point of origin is remote from the caster.

 

[Lanefan]

Clearly everyone falls prone face up or their neck twisted so that they can still see everything, otherwise prone would impose some sort of penalties on perception, which it does not.

Or the assumption is that because you can still move, if you do fall face down you'll roll over in order to see what's going on.