Here are some additional answers addressing how total cover and clear path must be considered together as a whole. I'd like to add them here:
@Dan_Dillon_1 Targeting spells/clear path: "Unoccupied space you can see" Does this imply targeting? Conjure fey across Wall of Force? @JeremyECrawford Unless a spell says otherwise, you can't cast it at someone or something behind total cover.
[...] Just because a rule makes it clear that you can't cast a spell at someone or something behind total cover (as confirmed by JC) does NOT mean that total cover is the ONLY thing that can interrupt your clear path for spell targeting.
Did you read just that tweet, or did you also see the second one I posted with the picture and the creatures between the caster and the target?
In the second tweet, there’s an example of half cover, and you can target the point behind the creatures—exactly like in your example with the foliage.
This second tweet is mixing several game concepts. A creature doesn't really occupy its entire space for the purposes of things like Line of Sight or Clear Path. A spellcaster might lean to the side and spot a clear path under the armpit or between the legs or something. This is also the reason why creatures do not generally provide full cover, although these two concepts are separate from each other.
What about Light or Darkness? Does the pane of glass stop their area effect?
The Light spell and the Darkness spell in 5e are both spells which create an Area of Effect. Indeed, both of these Areas of Effect are blocked by physical barriers, including glass barriers, if it's ruled that such a barrier provides total cover. In the case of the Darkness spell, it can spread around corners, but if it's a large enough barrier such that there are no corners to spread around then the effect is just blocked.
This does lead to some things in the game working a bit differently than in real life, but remember, these are magic spells. For example, if an area of total darkness is lit up by the light spell, but there is an obstacle such as a large wooden crate somewhere inside the area, then there will be a sliver of space behind this crate that remains in total darkness -- not dim light as we might expect, but total darkness. Another example is that the light from this spell will not extend through a glass window if that window is deemed to provide total cover, which is pretty weird.
Here is the important rule for this:
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.
However, I personally do not believe that every flimsy little thing such as a hanging sheet or a very thin pane of glass or a large palmetto leaf or a giant soap bubble should be deemed an "obstacle" that is capable of providing total cover. If a DM makes such a ruling, then AoE spells can extend through such barriers similar to how they can extend through an area of fog or some other environments that don't provide cover.
Keep in mind that this rule which governs how the effect of an AoE spreads to fill its area is separate from the clear path rule which governs whether or not a spellcaster is able to target whatever he is trying to target.
EDIT: I forgot to mention that the rules which govern how an AoE spreads, such as for the Light spell, are not necessarily the same rules which govern how natural (non-magical) light might illuminate an area.
For example, the torch object has this description: "A torch burns for 1 hour, providing bright light in a 20-foot radius and dim light for an additional 20 feet." None of this mentions what might or might not block this environmental effect and/or whether or not such light should spread around corners. I don't think that this is mentioned in any of the above-mentioned rules either. In my opinion, probably the best rule to apply for natural light sources is the Line of Sight rule -- if an object or effect blocks Line of Sight then it blocks light from that light source reaching those areas behind this object or effect. This leads to those slivers of total darkness behind obstacles again, but at least this would allow natural light to shine through windows, even when those windows are deemed to provide total cover.
What about Light or Darkness? Does the pane of glass stop their area effect?
I think you are referring to this rule (emphasis mine):
Areas of Effect (PHB, p. 204) [...] 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, as explained in chapter 9.
And then the rule about total cover from Chapter 9 that is mentioned:
A target with total cover can't be targeted directly by an attack or a spell, although some spells can reach such a target by including it in an area of effect. A target has total cover if it is completely concealed by an obstacle.
Darkness states "darkness spreads around corners", so depending on the size of the pane of glass, the effect shouldn't be blocked by that object. This is similar for the fireball spell, for example.
Light doesn't mention that it spreads around corners, so depending on the object should create some shadows in this case.
In my opinion, for boths spells, the DM should consider the size of the object and describe the final spell effect behind and/or around it accordingly.
EDIT: if the glass is transparent... you know... light can pass through it. When light hits a glass surface, some of it is reflected, but most passes through.
IRL The ammount of light passing through a glass depends on a number of factors like glass thickness and visual transmittance level, ambient or direct light source, lumen level and more.
In D&D the rules don't really address this so it would be up to DM how much light is emitted through glass, if any.
Darkness states "darkness spreads around corners", so depending on the size of the pane of glass, the effect shouldn't be blocked by that object. This is similar for the fireball spell, for example.
Light doesn't mention that it spreads around corners, so depending on the object should create some shadows in this case.
In my opinion, for boths spells, the DM should consider the size of the object and describe the final spell effect behind and/or around it accordingly.
EDIT: if the glass is transparent... you know... light can pass through it. When light hits a glass surface, some of it is reflected, but most passes through.
In every instance in this conversation the barrier is clear glass. Initially because a lot rides on "A target you can see".
Which evolved into - does this make sense? A light spell area effect being blocked by clear glass would be completely non-sensical.
Rollback Post to RevisionRollBack
"Sooner or later, your Players are going to smash your railroad into a sandbox."
-Vedexent
"real life is a super high CR."
-OboeLauren
"............anybody got any potatoes? We could drop a potato in each hole an' see which ones get viciously mauled by horrible monsters?"
Darkness states "darkness spreads around corners", so depending on the size of the pane of glass, the effect shouldn't be blocked by that object. This is similar for the fireball spell, for example.
Light doesn't mention that it spreads around corners, so depending on the object should create some shadows in this case.
In my opinion, for boths spells, the DM should consider the size of the object and describe the final spell effect behind and/or around it accordingly.
EDIT: if the glass is transparent... you know... light can pass through it. When light hits a glass surface, some of it is reflected, but most passes through.
In every instance in this conversation the barrier is clear glass. Initially because a lot rides on "A target you can see".
Which evolved into - does this make sense? A light spell area effect being blocked by clear glass would be completely non-sensical.
Dragons have the aerodynamic properties of toaster ovens, wingspans half the size necessary to generate lift for their mass, and absolutely no mechanism for performing any kind of areal maneuver sharper than a gentle curve, but they are apparently amazing flyers nonetheless.
Subterranean humanoid species somehow produce more melanin instead of less, and developed keener vision instead of evolving to do without sight altogether like most of the real subterranean species that actually exist.
No matter the construction materials or methods employed, nor the overall physical size or individual page count, absolutely every book in existence weighs exactly 5lbs, and costs precisely 25gp, unless it is a book specifically marketed to wizards and then it’s weight inexplicably drops by 40% and it’s cost automatically doubles.
Non-sensical is kinda baked directly into the DNA of D&D this edition, be it by either the 2014 or ‘24 version.
Darkness states "darkness spreads around corners", so depending on the size of the pane of glass, the effect shouldn't be blocked by that object. This is similar for the fireball spell, for example.
Light doesn't mention that it spreads around corners, so depending on the object should create some shadows in this case.
In my opinion, for boths spells, the DM should consider the size of the object and describe the final spell effect behind and/or around it accordingly.
EDIT: if the glass is transparent... you know... light can pass through it. When light hits a glass surface, some of it is reflected, but most passes through.
In every instance in this conversation the barrier is clear glass. Initially because a lot rides on "A target you can see".
Which evolved into - does this make sense? A light spell area effect being blocked by clear glass would be completely non-sensical.
I haven't changed my opinion, really: even if you can see the target, a glass can provide total cover.
For every spell, depending on the Range and the target, you need to consider the rule about having 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. [...]"
And then, if the spell covers an area, you need to consider this part of the rule about Areas of Effect: "[...] 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."
In the case of the light spell, the range is Touch, so in your example you could cast it (you have a Clear Path to an object you're holding, for example) but the AoE is affected by the pane of glass.
However... in this specific scenario, I was pointing out that light is light. So, if we're talking about a regular transparent piece of glass like those in the real world, the light should pass through it.
Now, if it were a stone wall in a dungeon? Yes, the wall would block the AoE of this spell.
But if we stick to RAW area of effect spells don't have specific rules for light trumping their general rule adjudication.
Area of Effect: 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.
The next image is just to illustrate my point of view and to receive your feedback (if you want to join this amazing party!)
Note: the ranges are simplified. Instead of 20 ft, it's a 10 ft radius for both bright and dim light. The inner circle represents bright light, while the outer circle represents dim light.
RAW, the pane of glass blocks the AoE of the light spell, so its right side won't be affected by the spell, thus limiting its AoE.
Common sense tells me that once the light is created, it should reach the other side of the glass pane, perhaps not fully, depending on the type of glass and other factors, which would be up to the DM to decide. However, this won't be due to the AoE itself, but because it's light in this specific case.
But it's true, strictly RAW, you could argue the light, being magical, cannot pass through the object even if it's transparent. So, for example, if the right side of the glass were natural darkness, that side would remain dark.
But it's true, strictly RAW, you could argue the light, being magical, cannot pass through the object even if it's transparent. So, for example, if the right side of the glass were natural darkness, that side would remain dark.
Yep, this is the answer. Magic can be a bit weird. But that's the key to this one -- the light spell isn't just light, it's magic. The light that's created by that spell is just the effect of that AoE that the spell creates. Since the AoE of a spell cannot penetrate total cover then if this glass is deemed to provide total cover then the light from this spell just stops there and the interior of that building through this window remains obscured by darkness.
If instead the exterior of the building is daytime and filled with natural light then this light would illuminate at least a portion of the interior. Likewise, if instead of using a magic spell, a person simply lit a torch during nighttime and shined that torch up against the window then they would be able to see some portions of the interior space.
Note that this all depends on the glass for this window providing total cover:
A target has total cover if it is completely concealedby an obstacle.
Although this isn't a popular interpretation, to me, this rule has two parts to it:
1. A creature's body must be fully concealed.
2. It must be concealed by an obstacle.
Although it's never formally defined, the term "obstacle" appears 6 times within the section of rules that describes Cover. Many examples are given of objects that should be considered to be obstacles for the purposes of this defensive protection that is provided by Cover. In my opinion, whether or not an object should count as an "obstacle" is to be adjudicated by the DM.
For example, if a creature drapes a bedsheet over his head or he holds it up in front of him while he is walking around, that creature should not enjoy the benefits of total cover from missile attacks -- at least, that's how I would rule it and I believe it's the DM's job to make this decision.
To me, a pane of glass for a window of a building is questionable regarding whether or not it should count as an obstacle that provides total cover. I think that it should depend on the particular glass in question, as decided by the DM.
If a DM decides that the glass is flimsy enough that it should not provide total cover from missile attacks, then this lack of total cover would also impact whether or not it is able to block the effects of an AoE. If it does not provide total cover then the AoE should be able to penetrate through that obstruction similar to how it should penetrate through a cloud of fog. But, as I mentioned earlier, in my opinion the lack of total cover does not necessarily mean that you have a Clear Path to your target although the converse is definitely true by rule -- if there IS total cover then you do NOT have a Clear Path.
So, depending on the glass, I might rule that the glass provides half-cover which does not block the effects of an AoE but it DOES interrupt your Clear Path. Glass like this would be very easy to break so there's always the option to use an action to break the glass first and then cast your spell after that since the Clear Path is now available. I would give glass that is flimsy enough to only provide half cover only 2 AC (after all, half cover gives a +2 bonus to AC) and maybe 1 or 2 HP. Pretty much always breaks if someone tries to break it. Glass that's quite a bit sturdier than that should just provide total cover.
IRL The ammount of light passing through a glass depends on a number of factors like glass thickness and visual transmittance level, ambient or direct light source, lumen level and more.
In D&D the rules don't really address this so it would be up to DM how much light is emitted through glass, if any.
Interesting question ...
The Light cantrip creates a light source equivalent to a torch.
Does this mean that you could hold a torch up to the windows of a darkened building and use it to illuminate the inside but that an object with the light cantrip would not illuminate the inside?
Personally, I'd probably rule that the light cantrip spell is creating a source of light and treat the light the same as any other light source in terms of what it can and can not illuminate. Unless the spell description (like the Darkness spell) defines a specific alternate behavior.
It's not defined either way. But a light source emitting in a radius is diffused ambient light, not direct light so the DM is free to adjudicate it in any way but the rules don't offer much guidance on the subject is all i can say.
The next image is just to illustrate my point of view and to receive your feedback (if you want to join this amazing party!)
Note: the ranges are simplified. Instead of 20 ft, it's a 10 ft radius for both bright and dim light. The inner circle represents bright light, while the outer circle represents dim light.
RAW, the pane of glass blocks the AoE of the light spell, so its right side won't be affected by the spell, thus limiting its AoE.
Common sense tells me that once the light is created, it should reach the other side of the glass pane, perhaps not fully, depending on the type of glass and other factors, which would be up to the DM to decide. However, this won't be due to the AoE itself, but because it's light in this specific case.
But it's true, strictly RAW, you could argue the light, being magical, cannot pass through the object even if it's transparent. So, for example, if the right side of the glass were natural darkness, that side would remain dark.
How is that RAW? An AOE extends until blocked. But in which rule does it say a pane of glass blocks light? That's explicitly what it doesn't block.
Rollback Post to RevisionRollBack
I'm probably laughing.
It is apparently so hard to program Aberrant Mind and Clockwork Soul spell-swapping into dndbeyond they had to remake the game without it rather than implement it.
Non-magical light passes through glass as expected. But if the light is the result of a magic spell's AoE, then it's just another magical effect and those are blocked by physical barriers as per the rule for an AoE.
Non-magical light passes through glass as expected. But if the light is the result of a magic spell's AoE, then it's just another magical effect and those are blocked by physical barriers as per the rule for an AoE.
Can you quote the rule excerpt that says that? Because I can't find it.
I can only find it saying that barriers can block the effects of the aoe. But since glass doesn't block light it wouldn't be a barrier to the effect of the light spell.
Rollback Post to RevisionRollBack
I'm probably laughing.
It is apparently so hard to program Aberrant Mind and Clockwork Soul spell-swapping into dndbeyond they had to remake the game without it rather than implement it.
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Did you read just that tweet, or did you also see the second one I posted with the picture and the creatures between the caster and the target?
In the second tweet, there’s an example of half cover, and you can target the point behind the creatures—exactly like in your example with the foliage.
This second tweet is mixing several game concepts. A creature doesn't really occupy its entire space for the purposes of things like Line of Sight or Clear Path. A spellcaster might lean to the side and spot a clear path under the armpit or between the legs or something. This is also the reason why creatures do not generally provide full cover, although these two concepts are separate from each other.
To target something, you must have a clear path to it, so it can't be behind total cover.
A target has total cover if it is completely concealed by an obstacle.
A target completely concealed by an obstacle likely have no clear path to it.
Things that provide half cover, three-quarters cover, lightly or heavily obscured don't typically makes you completely concealed by an obstacle.
What about Light or Darkness? Does the pane of glass stop their area effect?
"Sooner or later, your Players are going to smash your railroad into a sandbox."
-Vedexent
"real life is a super high CR."
-OboeLauren
"............anybody got any potatoes? We could drop a potato in each hole an' see which ones get viciously mauled by horrible monsters?"
-Ilyara Thundertale
The Light spell and the Darkness spell in 5e are both spells which create an Area of Effect. Indeed, both of these Areas of Effect are blocked by physical barriers, including glass barriers, if it's ruled that such a barrier provides total cover. In the case of the Darkness spell, it can spread around corners, but if it's a large enough barrier such that there are no corners to spread around then the effect is just blocked.
This does lead to some things in the game working a bit differently than in real life, but remember, these are magic spells. For example, if an area of total darkness is lit up by the light spell, but there is an obstacle such as a large wooden crate somewhere inside the area, then there will be a sliver of space behind this crate that remains in total darkness -- not dim light as we might expect, but total darkness. Another example is that the light from this spell will not extend through a glass window if that window is deemed to provide total cover, which is pretty weird.
Here is the important rule for this:
However, I personally do not believe that every flimsy little thing such as a hanging sheet or a very thin pane of glass or a large palmetto leaf or a giant soap bubble should be deemed an "obstacle" that is capable of providing total cover. If a DM makes such a ruling, then AoE spells can extend through such barriers similar to how they can extend through an area of fog or some other environments that don't provide cover.
Keep in mind that this rule which governs how the effect of an AoE spreads to fill its area is separate from the clear path rule which governs whether or not a spellcaster is able to target whatever he is trying to target.
EDIT: I forgot to mention that the rules which govern how an AoE spreads, such as for the Light spell, are not necessarily the same rules which govern how natural (non-magical) light might illuminate an area.
For example, the torch object has this description: "A torch burns for 1 hour, providing bright light in a 20-foot radius and dim light for an additional 20 feet." None of this mentions what might or might not block this environmental effect and/or whether or not such light should spread around corners. I don't think that this is mentioned in any of the above-mentioned rules either. In my opinion, probably the best rule to apply for natural light sources is the Line of Sight rule -- if an object or effect blocks Line of Sight then it blocks light from that light source reaching those areas behind this object or effect. This leads to those slivers of total darkness behind obstacles again, but at least this would allow natural light to shine through windows, even when those windows are deemed to provide total cover.
I think you are referring to this rule (emphasis mine):
And then the rule about total cover from Chapter 9 that is mentioned:
Darkness states "darkness spreads around corners", so depending on the size of the pane of glass, the effect shouldn't be blocked by that object. This is similar for the fireball spell, for example.
Light doesn't mention that it spreads around corners, so depending on the object should create some shadows in this case.
In my opinion, for boths spells, the DM should consider the size of the object and describe the final spell effect behind and/or around it accordingly.
EDIT: if the glass is transparent... you know... light can pass through it. When light hits a glass surface, some of it is reflected, but most passes through.
IRL The ammount of light passing through a glass depends on a number of factors like glass thickness and visual transmittance level, ambient or direct light source, lumen level and more.
In D&D the rules don't really address this so it would be up to DM how much light is emitted through glass, if any.
maybe used mirrors
mirrors is be like glass
merlin the warlock
In every instance in this conversation the barrier is clear glass. Initially because a lot rides on "A target you can see".
Which evolved into - does this make sense? A light spell area effect being blocked by clear glass would be completely non-sensical.
"Sooner or later, your Players are going to smash your railroad into a sandbox."
-Vedexent
"real life is a super high CR."
-OboeLauren
"............anybody got any potatoes? We could drop a potato in each hole an' see which ones get viciously mauled by horrible monsters?"
-Ilyara Thundertale
Dragons have the aerodynamic properties of toaster ovens, wingspans half the size necessary to generate lift for their mass, and absolutely no mechanism for performing any kind of areal maneuver sharper than a gentle curve, but they are apparently amazing flyers nonetheless.
Subterranean humanoid species somehow produce more melanin instead of less, and developed keener vision instead of evolving to do without sight altogether like most of the real subterranean species that actually exist.
No matter the construction materials or methods employed, nor the overall physical size or individual page count, absolutely every book in existence weighs exactly 5lbs, and costs precisely 25gp, unless it is a book specifically marketed to wizards and then it’s weight inexplicably drops by 40% and it’s cost automatically doubles.
Non-sensical is kinda baked directly into the DNA of D&D this edition, be it by either the 2014 or ‘24 version.
Creating Epic Boons on DDB
DDB Buyers' Guide
Hardcovers, DDB & You
Content Troubleshooting
I haven't changed my opinion, really: even if you can see the target, a glass can provide total cover.
For every spell, depending on the Range and the target, you need to consider the rule about having 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. [...]"
And then, if the spell covers an area, you need to consider this part of the rule about Areas of Effect: "[...] 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."
In the case of the light spell, the range is Touch, so in your example you could cast it (you have a Clear Path to an object you're holding, for example) but the AoE is affected by the pane of glass.
However... in this specific scenario, I was pointing out that light is light. So, if we're talking about a regular transparent piece of glass like those in the real world, the light should pass through it.
Now, if it were a stone wall in a dungeon? Yes, the wall would block the AoE of this spell.
But if we stick to RAW area of effect spells don't have specific rules for light trumping their general rule adjudication.
The next image is just to illustrate my point of view and to receive your feedback (if you want to join this amazing party!)
Note: the ranges are simplified. Instead of 20 ft, it's a 10 ft radius for both bright and dim light. The inner circle represents bright light, while the outer circle represents dim light.
RAW, the pane of glass blocks the AoE of the light spell, so its right side won't be affected by the spell, thus limiting its AoE.
Common sense tells me that once the light is created, it should reach the other side of the glass pane, perhaps not fully, depending on the type of glass and other factors, which would be up to the DM to decide. However, this won't be due to the AoE itself, but because it's light in this specific case.
But it's true, strictly RAW, you could argue the light, being magical, cannot pass through the object even if it's transparent. So, for example, if the right side of the glass were natural darkness, that side would remain dark.
Yep, this is the answer. Magic can be a bit weird. But that's the key to this one -- the light spell isn't just light, it's magic. The light that's created by that spell is just the effect of that AoE that the spell creates. Since the AoE of a spell cannot penetrate total cover then if this glass is deemed to provide total cover then the light from this spell just stops there and the interior of that building through this window remains obscured by darkness.
If instead the exterior of the building is daytime and filled with natural light then this light would illuminate at least a portion of the interior. Likewise, if instead of using a magic spell, a person simply lit a torch during nighttime and shined that torch up against the window then they would be able to see some portions of the interior space.
Note that this all depends on the glass for this window providing total cover:
Although this isn't a popular interpretation, to me, this rule has two parts to it:
1. A creature's body must be fully concealed.
2. It must be concealed by an obstacle.
Although it's never formally defined, the term "obstacle" appears 6 times within the section of rules that describes Cover. Many examples are given of objects that should be considered to be obstacles for the purposes of this defensive protection that is provided by Cover. In my opinion, whether or not an object should count as an "obstacle" is to be adjudicated by the DM.
For example, if a creature drapes a bedsheet over his head or he holds it up in front of him while he is walking around, that creature should not enjoy the benefits of total cover from missile attacks -- at least, that's how I would rule it and I believe it's the DM's job to make this decision.
To me, a pane of glass for a window of a building is questionable regarding whether or not it should count as an obstacle that provides total cover. I think that it should depend on the particular glass in question, as decided by the DM.
If a DM decides that the glass is flimsy enough that it should not provide total cover from missile attacks, then this lack of total cover would also impact whether or not it is able to block the effects of an AoE. If it does not provide total cover then the AoE should be able to penetrate through that obstruction similar to how it should penetrate through a cloud of fog. But, as I mentioned earlier, in my opinion the lack of total cover does not necessarily mean that you have a Clear Path to your target although the converse is definitely true by rule -- if there IS total cover then you do NOT have a Clear Path.
So, depending on the glass, I might rule that the glass provides half-cover which does not block the effects of an AoE but it DOES interrupt your Clear Path. Glass like this would be very easy to break so there's always the option to use an action to break the glass first and then cast your spell after that since the Clear Path is now available. I would give glass that is flimsy enough to only provide half cover only 2 AC (after all, half cover gives a +2 bonus to AC) and maybe 1 or 2 HP. Pretty much always breaks if someone tries to break it. Glass that's quite a bit sturdier than that should just provide total cover.
Interesting question ...
The Light cantrip creates a light source equivalent to a torch.
Does this mean that you could hold a torch up to the windows of a darkened building and use it to illuminate the inside but that an object with the light cantrip would not illuminate the inside?
Personally, I'd probably rule that the light cantrip spell is creating a source of light and treat the light the same as any other light source in terms of what it can and can not illuminate. Unless the spell description (like the Darkness spell) defines a specific alternate behavior.
It's not defined either way. But a light source emitting in a radius is diffused ambient light, not direct light so the DM is free to adjudicate it in any way but the rules don't offer much guidance on the subject is all i can say.
How is that RAW? An AOE extends until blocked. But in which rule does it say a pane of glass blocks light? That's explicitly what it doesn't block.
I'm probably laughing.
It is apparently so hard to program Aberrant Mind and Clockwork Soul spell-swapping into dndbeyond they had to remake the game without it rather than implement it.
Non-magical light passes through glass as expected. But if the light is the result of a magic spell's AoE, then it's just another magical effect and those are blocked by physical barriers as per the rule for an AoE.
Can you quote the rule excerpt that says that? Because I can't find it.
I can only find it saying that barriers can block the effects of the aoe. But since glass doesn't block light it wouldn't be a barrier to the effect of the light spell.
I'm probably laughing.
It is apparently so hard to program Aberrant Mind and Clockwork Soul spell-swapping into dndbeyond they had to remake the game without it rather than implement it.