When using the grid rules, the Dungeon Master's Guide says to choose an intersection of squares as the point of origin of an area of effect. But what if the point of origin is yourself? What do you do then?
Do you set the point of origin to a corner of your space? If so, how can you fire lightning bolt in a straight line at a row of enemies east of you?
Do you set the point of origin to the center of your space? Doesn't that seriously limit the effectiveness of thunderwave by effectively lowering the length of one side of the cube by 5 feet?
Does an intersection of squares only refer to the corner of a square? Or is it anywhere on the side of a square, because two squares meet?
I would rule an "intersection" of squares is anywhere on the line boundary of a square (as you said, its the intersection between at least two). For self targeted spells, the square in question would have to be the square you are standing in.
When using the grid rules, the Dungeon Master's Guide says to choose an intersection of squares as the point of origin of an area of effect. But what if the point of origin is yourself? What do you do then? (1)
Do you set the point of origin to a corner of your space? If so, how can you fire lightning bolt in a straight line at a row of enemies east of you? (2)
Do you set the point of origin to the center of your space? Doesn't that seriously limit the effectiveness of thunderwave by effectively lowering the length of one side of the cube by 5 feet? (3)
Does an intersection of squares only refer to the corner of a square? Or is it anywhere on the side of a square, because two squares meet? (4)
When the range of a spell is "Self", then either the square you currently occupy, or a corner/edge of your square, is the point of origin.
It really just comes down to what you think will be best for a particular spell. If it's a line/cone, you probably want to use a corner/edge.
If the spell specifically calls out the point of origin as centered on you, then the origin is the center of your square.
An AoE affects squares that are at least 50% covered by the AoE. If you use a corner, and projects straight down the grid line, the squares on each side are affected.
Yes, it is centered on you, as that's what the spell specifically calls for. No, it does not seriously limit Thunderwave... the spell is intended to affect everything around you.
It typically means the corner, but it can mean edge as well. Keep in mind that using an edge is basically the same as designating yourself as the origin, without including your square in the effect. Depending on the specific spell, that's an important distinction.
TL;DR read the spell carefully, and just ask your DM if you're unsure. Here's the PHB section on AoEs.
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You don't know what fear is until you've witnessed a drunk bird divebombing you while carrying a screaming Kobold throwing fire anywhere and everywhere.
That doesn't apply to effects that call for a specific shape such as the cube in Thunderwave. The cube is 15'x15'x15' no matter where the origin could be, and the spell specifically calls for it to be centered on you. That means it only projects to the caster's directly adjacent (including diagonal) squares.
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You don't know what fear is until you've witnessed a drunk bird divebombing you while carrying a screaming Kobold throwing fire anywhere and everywhere.
That doesn't apply to effects that call for a specific shape such as the cube in Thunderwave. The cube is 15'x15'x15' no matter where the origin could be, and the spell specifically calls for it to be centered on you. That means it only projects to the caster's directly adjacent (including diagonal) squares.
This bit about thunderwave isn't actually true. The spell states that it originates from you, not that it is centered on you, meaning the caster is somewhere on the cube's surface. So if the origin point were the center of the caster's space, and they were trying to direct the cube eastward, the three spaces on the caster's side of the cube would be unaffected, because it is a non-circular AOE and only half of each space is occupied. The three spaces on the opposite end would similarly be unaffected.
By having the spell originate from inside the area of the square, the 15'x15'x15' cube effectively turns into a 15'x15'x10' rectangular prism. Is it viable? Yeah, probably. But it's still kind of weird, right?
If the effect in question is a 30 foot sphere centered on the center of the caster's space, then I should point out that most of those squares in the outer ring are actually occupied by less than half of the sphere in question, meaning they are unaffected. So it would actually be more optimal in this case to center it on the corner of the caster's square.
An AoE affects squares that are at least 50% covered by the AoE. If you use a corner, and [lightning bolt] projects straight down the grid line, the squares on each side are affected.
That rule only applies to circular AoEs. For us to consider a line AoE to be circular, we have to think in three dimensions. If a cross-section of the line in question is indeed a circle with a diameter of 5 feet (which is, as I understand it, how it appears), then the spell is unable to affect any squares if aimed directly east, as a half-circle within each cross-section isn't enough to fill even half of any space that it touches.
If the effect in question is a 30 foot sphere centered on the center of the caster's space, then I should point out that most of those squares in the outer ring are actually occupied by less than half of the sphere in question, meaning they are unaffected. So it would actually be more optimal in this case to center it on the corner of the caster's square.
I only highlighter the ones that would be effected.
That doesn't apply to effects that call for a specific shape such as the cube in Thunderwave. The cube is 15'x15'x15' no matter where the origin could be, and the spell specifically calls for it to be centered on you. That means it only projects to the caster's directly adjacent (including diagonal) squares.
This bit about thunderwave isn't actually true. The spell states that it originates from you, not that it is centered on you, meaning the caster is somewhere on the cube's surface. So if the origin point were the center of the caster's space, and they were trying to direct the cube eastward, the three spaces on the caster's side of the cube would be unaffected, because it is a non-circular AOE and only half of each space is occupied. The three spaces on the opposite end would similarly be unaffected.
By having the spell originate from inside the area of the square, the 15'x15'x15' cube effectively turns into a 15'x15'x10' rectangular prism. Is it viable? Yeah, probably. But it's still kind of weird, right?
Huh... you're right! Originating from the caster does mean the space the caster occupies is the origin, but what I missed was that the cube AoE's origin is specifically on an outer surface. That actually changes my personal opinion of the spell dramatically.
All AoEs that cover 50% or more of a square include that square in the effect, not just circles.
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You don't know what fear is until you've witnessed a drunk bird divebombing you while carrying a screaming Kobold throwing fire anywhere and everywhere.
That doesn't apply to effects that call for a specific shape such as the cube in Thunderwave. The cube is 15'x15'x15' no matter where the origin could be, and the spell specifically calls for it to be centered on you. That means it only projects to the caster's directly adjacent (including diagonal) squares.
This bit about thunderwave isn't actually true. The spell states that it originates from you, not that it is centered on you, meaning the caster is somewhere on the cube's surface. So if the origin point were the center of the caster's space, and they were trying to direct the cube eastward, the three spaces on the caster's side of the cube would be unaffected, because it is a non-circular AOE and only half of each space is occupied. The three spaces on the opposite end would similarly be unaffected.
By having the spell originate from inside the area of the square, the 15'x15'x15' cube effectively turns into a 15'x15'x10' rectangular prism. Is it viable? Yeah, probably. But it's still kind of weird, right?
Huh... you're right! Originating from the caster does mean the space the caster occupies is the origin, but what I missed was that the cube AoE's origin is specifically on an outer surface. That actually changes my personal opinion of the spell dramatically.
All AoEs that cover 50% or more of a square include that square in the effect, not just circles.
The bold is very true...cones and lines can be shot at different angles, so the 50% rule will definitely apply when you go “off grid” or even on grid if you send the line down a boundary between squares
All AoEs that cover 50% or more of a square include that square in the effect, not just circles.
Where are you getting this? In the DMG, Chapter 8 > Combat > Areas of Effect, it states that "If an area of effect is circular and covers at least half a square, it affects that square." And of all the AoE types provided in the PHB, the only one that I wouldn't consider to be circular in any way is a cube.
And that, in any case, playing on a grid is only an option in itself, and getting rid of it also makes the game (at least IMHO) much more what it is intended for, i.e. a roleplaying game, rather than a combat board game like the previous editions...
Playing TotM is fine in most cases but once you throw in spells with area effects or line effects like lightning bolt a grid or hex map becomes a greater benefit. It makes it much more clear who will be hit.
Yes, it turns play more tactical but once you involve more than 6 participants, working out AOE in your mind gets hard.
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"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?"
All AoEs that cover 50% or more of a square include that square in the effect, not just circles
No printed rule says exactly that.
From the DMG Using Miniatures: "If an area of effect is circular and covers at least half a square, it affects that square."
From XGtE Using a Template: "If any part of a square is under the template, that square is included in the area of effect."
From XGtE Using Tokens: "If an area’s token is in a square, that square is included in the area of effect. It’s that simple."
But, after discussing this at length in another thread, I choose to use a set of rules consistently at my table and let others use their rules as they please. It is certainly reasonable to allow any AOE that covers more than 50% of a square to include that square at your table. It is also reasonable to use the diagonal counting rules and allow round area of effects to fill a square. TotM is a reasonable way to go. Many different choices are reasonable.
ToTM is very easy, you just think about the situation and ask the DM "can I hit the three kobolds over there with my lightning bolt ?" and the DM answers "actually, you can get 4, they are close packed" or "no, you cam get only 2, they are two far apart", you decide whether you cast the spell and there you go.
Heh, you must have a spectacular DM or a bunch of like minded players, because that is not my experience. My experience is more like:
Player1: Can I hit 3 kobolds with my lightning bolt?
DM: Actually, you can get 4, they are close packed.
Player1: Well, if I move first, can I hit more?
DM: No.
Player1: Instead, if I cast fireball, can I hit more than 4?
DM: Yes, but you'll hit Player 2 as well.
Player1: How many more?
DM: 2 more, so 6 total plus your ally.
Player1: Hmm, do any of the kobolds look stronger than the others? So if I shift my fireball to not hit Player2, so as to only hit 4 kobolds, can I be sure to hit the stronger ones?
DM: You can't tell if there are stronger ones.
Player1: Never mind then, I'll save my spell slots to be sure I hit more of them. Player2, on your turn can you tell the DM you move in such a way as to block the kobolds from getting past you and attacking me, but also in such a way that if I cast fireball I can hit all of them without hitting you?
Player2: Sure. Whatever it takes to get to my turn.
Player1: Then I shoot a firebolt.
...
Player3: I cast Moonbeam right in front of player 2.
DM: Ok, there will be 6 in the Moonbeam when it is cast.
Player1: Wait, what!? You said I could only hit 6 with my fireball if I also hit player2? What gives?
DM: Oh, did I say that? Sorry, hard to keep this straight in my head. Ok, there will only be 4 in your Moonbeam with it is cast.
All AoEs that cover 50% or more of a square include that square in the effect, not just circles
No printed rule says exactly that.
From the DMG Using Miniatures: "If an area of effect is circular and covers at least half a square, it affects that square."
From XGtE Using a Template: "If any part of a square is under the template, that square is included in the area of effect."
From XGtE Using Tokens: "If an area’s token is in a square, that square is included in the area of effect. It’s that simple."
But, after discussing this at length in another thread, I choose to use a set of rules consistently at my table and let others use their rules as they please. It is certainly reasonable to allow any AOE that covers more than 50% of a square to include that square at your table. It is also reasonable to use the diagonal counting rules and allow round area of effects to fill a square. TotM is a reasonable way to go. Many different choices are reasonable.
Since we're quoting XGtE...
Using a Template. To use an area-of-effect template, apply it to the grid. If the terrain is flat, you can lay it on the surface; otherwise, hold the template above the surface and take note of which squares it covers or partially covers. If any part of a square is under the template, that square is included in the area of effect. If a creature’s miniature is in an affected square, that creature is in the area. Being adjacent to the edge of the template isn’t enough for a square to be included in the area of effect; the square must be entirely or partly covered by the template.
You can also use this method without a grid. If you do so, a creature is included in an area of effect if any part of the miniature’s base is overlapped by the template.
When you place a template, follow all the rules in the Player’s Handbook for placing the associated area of effect. If an area of effect, such as a cone or a line, originates from a spellcaster, the template should extend out from the caster and be positioned however the caster likes within the bounds of the rules.
Soo.. yeah, lines too.
Although, I do get what you're saying. If I'm casting a line spell that's supposed to be 5 feet wide, and I send it straight down the grid line from my corner, that's basically turning it into a line spell that's effectively 10 feet wide. Feels cheesy, but that does seem to be a valid usage. :/
You don't know what fear is until you've witnessed a drunk bird divebombing you while carrying a screaming Kobold throwing fire anywhere and everywhere.
When using the grid rules, the Dungeon Master's Guide says to choose an intersection of squares as the point of origin of an area of effect. But what if the point of origin is yourself? What do you do then?
Do you set the point of origin to a corner of your space? If so, how can you fire lightning bolt in a straight line at a row of enemies east of you?
Do you set the point of origin to the center of your space? Doesn't that seriously limit the effectiveness of thunderwave by effectively lowering the length of one side of the cube by 5 feet?
Does an intersection of squares only refer to the corner of a square? Or is it anywhere on the side of a square, because two squares meet?
I would rule an "intersection" of squares is anywhere on the line boundary of a square (as you said, its the intersection between at least two). For self targeted spells, the square in question would have to be the square you are standing in.
Xanatar's Guide to Everything p.86-87
playing since 1986
TL;DR read the spell carefully, and just ask your DM if you're unsure. Here's the PHB section on AoEs.
You don't know what fear is until you've witnessed a drunk bird divebombing you while carrying a screaming Kobold throwing fire anywhere and everywhere.
30’ radius = 96 potential Targets:
🔲🔲🔲🔲🔲🔲🔲🔲🔲🔲🔲🔲🔲🔲🔲🔲.
🔲🔲🔲🔲🔲🔲🔲🔲🔲🔲🔲🔲🔲🔲🔲🔲.
🔲🔲🔲🔲🔲🔲🔲🟥🟥🔲🔲🔲🔲🔲🔲🔲.
🔲🔲🔲🔲🔲🟥🟥🟥🟥🟥🟥🔲🔲🔲🔲🔲.
🔲🔲🔲🔲🟥🟥🟥🟥🟥🟥🟥🟥🔲🔲🔲🔲.
🔲🔲🔲🟥🟥🟥🟥🟥🟥🟥🟥🟥🟥🔲🔲🔲.
🔲🔲🔲🟥🟥🟥🟥🟥🟥🟥🟥🟥🟥🔲🔲🔲.
🔲🔲🟥🟥🟥🟥🟥🟥🟥🟥🟥🟥🟥🟥🔲🔲.
🔲🔲🟥🟥🟥🟥🟥🟥🟥🟥🟥🟥🟥🟥🔲🔲.
🔲🔲🔲🟥🟥🟥🟥🟥🟥🟥🟥🟥🟥🔲🔲🔲.
🔲🔲🔲🟥🟥🟥🟥🟥🟥🟥🟥🟥🟥🔲🔲🔲.
🔲🔲🔲🔲🟥🟥🟥🟥🟥🟥🟥🟥🔲🔲🔲🔲.
🔲🔲🔲🔲🔲🟥🟥🟥🟥🟥🟥🔲🔲🔲🔲🔲.
🔲🔲🔲🔲🔲🔲🔲🟥🟥🔲🔲🔲🔲🔲🔲🔲.
🔲🔲🔲🔲🔲🔲🔲🔲🔲🔲🔲🔲🔲🔲🔲🔲.
🔲🔲🔲🔲🔲🔲🔲🔲🔲🔲🔲🔲🔲🔲🔲🔲.
30’ from caster = 120 potential Targets:
🔲🔲🔲🔲🔲🔲🔲🔲🔲🔲🔲🔲🔲🔲🔲🔲🔲.
🔲🔲🔲🔲🔲🔲🔲🔲🔲🔲🔲🔲🔲🔲🔲🔲🔲.
🔲🔲🔲🔲🔲🔲🔲🟥🟥🟥🔲🔲🔲🔲🔲🔲🔲.
🔲🔲🔲🔲🔲🟥🟥🟥🟥🟥🟥🟥🔲🔲🔲🔲🔲.
🔲🔲🔲🔲🟥🟥🟥🟥🟥🟥🟥🟥🟥🔲🔲🔲🔲.
🔲🔲🔲🟥🟥🟥🟥🟥🟥🟥🟥🟥🟥🟥🔲🔲🔲.
🔲🔲🔲🟥🟥🟥🟥🟥🟥🟥🟥🟥🟥🟥🔲🔲🔲.
🔲🔲🟥🟥🟥🟥🟥🟥🟥🟥🟥🟥🟥🟥🟥🔲🔲.
🔲🔲🟥🟥🟥🟥🟥🟥🧙🟥🟥🟥🟥🟥🟥🔲🔲.
🔲🔲🟥🟥🟥🟥🟥🟥🟥🟥🟥🟥🟥🟥🟥🔲🔲.
🔲🔲🔲🟥🟥🟥🟥🟥🟥🟥🟥🟥🟥🟥🔲🔲🔲.
🔲🔲🔲🟥🟥🟥🟥🟥🟥🟥🟥🟥🟥🟥🔲🔲🔲.
🔲🔲🔲🔲🟥🟥🟥🟥🟥🟥🟥🟥🟥🔲🔲🔲🔲.
🔲🔲🔲🔲🔲🟥🟥🟥🟥🟥🟥🟥🔲🔲🔲🔲🔲.
🔲🔲🔲🔲🔲🔲🔲🟥🟥🟥🔲🔲🔲🔲🔲🔲🔲.
🔲🔲🔲🔲🔲🔲🔲🔲🔲🔲🔲🔲🔲🔲🔲🔲🔲.
🔲🔲🔲🔲🔲🔲🔲🔲🔲🔲🔲🔲🔲🔲🔲🔲🔲.
Don’t cheat yourself.
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That doesn't apply to effects that call for a specific shape such as the cube in Thunderwave. The cube is 15'x15'x15' no matter where the origin could be, and the spell specifically calls for it to be centered on you. That means it only projects to the caster's directly adjacent (including diagonal) squares.
You don't know what fear is until you've witnessed a drunk bird divebombing you while carrying a screaming Kobold throwing fire anywhere and everywhere.
Basic rule is that the grid is supposed to be helpful, NOT part of the rules.
Use the grid and then ask the DM "Can I do this?" rather than asking us.
This bit about thunderwave isn't actually true. The spell states that it originates from you, not that it is centered on you, meaning the caster is somewhere on the cube's surface. So if the origin point were the center of the caster's space, and they were trying to direct the cube eastward, the three spaces on the caster's side of the cube would be unaffected, because it is a non-circular AOE and only half of each space is occupied. The three spaces on the opposite end would similarly be unaffected.
By having the spell originate from inside the area of the square, the 15'x15'x15' cube effectively turns into a 15'x15'x10' rectangular prism. Is it viable? Yeah, probably. But it's still kind of weird, right?
If the effect in question is a 30 foot sphere centered on the center of the caster's space, then I should point out that most of those squares in the outer ring are actually occupied by less than half of the sphere in question, meaning they are unaffected. So it would actually be more optimal in this case to center it on the corner of the caster's square.
That rule only applies to circular AoEs. For us to consider a line AoE to be circular, we have to think in three dimensions. If a cross-section of the line in question is indeed a circle with a diameter of 5 feet (which is, as I understand it, how it appears), then the spell is unable to affect any squares if aimed directly east, as a half-circle within each cross-section isn't enough to fill even half of any space that it touches.
I only highlighter the ones that would be effected.
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Huh... you're right! Originating from the caster does mean the space the caster occupies is the origin, but what I missed was that the cube AoE's origin is specifically on an outer surface. That actually changes my personal opinion of the spell dramatically.
All AoEs that cover 50% or more of a square include that square in the effect, not just circles.
You don't know what fear is until you've witnessed a drunk bird divebombing you while carrying a screaming Kobold throwing fire anywhere and everywhere.
The bold is very true...cones and lines can be shot at different angles, so the 50% rule will definitely apply when you go “off grid” or even on grid if you send the line down a boundary between squares
Where are you getting this? In the DMG, Chapter 8 > Combat > Areas of Effect, it states that "If an area of effect is circular and covers at least half a square, it affects that square." And of all the AoE types provided in the PHB, the only one that I wouldn't consider to be circular in any way is a cube.
Which is why I use hexes. They are much more intuitive.
"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
Playing TotM is fine in most cases but once you throw in spells with area effects or line effects like lightning bolt a grid or hex map becomes a greater benefit. It makes it much more clear who will be hit.
Yes, it turns play more tactical but once you involve more than 6 participants, working out AOE in your mind gets hard.
"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
No printed rule says exactly that.
From the DMG Using Miniatures: "If an area of effect is circular and covers at least half a square, it affects that square."
From XGtE Using a Template: "If any part of a square is under the template, that square is included in the area of effect."
From XGtE Using Tokens: "If an area’s token is in a square, that square is included in the area of effect. It’s that simple."
But, after discussing this at length in another thread, I choose to use a set of rules consistently at my table and let others use their rules as they please. It is certainly reasonable to allow any AOE that covers more than 50% of a square to include that square at your table. It is also reasonable to use the diagonal counting rules and allow round area of effects to fill a square. TotM is a reasonable way to go. Many different choices are reasonable.
Heh, you must have a spectacular DM or a bunch of like minded players, because that is not my experience. My experience is more like:
Player1: Can I hit 3 kobolds with my lightning bolt?
DM: Actually, you can get 4, they are close packed.
Player1: Well, if I move first, can I hit more?
DM: No.
Player1: Instead, if I cast fireball, can I hit more than 4?
DM: Yes, but you'll hit Player 2 as well.
Player1: How many more?
DM: 2 more, so 6 total plus your ally.
Player1: Hmm, do any of the kobolds look stronger than the others? So if I shift my fireball to not hit Player2, so as to only hit 4 kobolds, can I be sure to hit the stronger ones?
DM: You can't tell if there are stronger ones.
Player1: Never mind then, I'll save my spell slots to be sure I hit more of them. Player2, on your turn can you tell the DM you move in such a way as to block the kobolds from getting past you and attacking me, but also in such a way that if I cast fireball I can hit all of them without hitting you?
Player2: Sure. Whatever it takes to get to my turn.
Player1: Then I shoot a firebolt.
...
Player3: I cast Moonbeam right in front of player 2.
DM: Ok, there will be 6 in the Moonbeam when it is cast.
Player1: Wait, what!? You said I could only hit 6 with my fireball if I also hit player2? What gives?
DM: Oh, did I say that? Sorry, hard to keep this straight in my head. Ok, there will only be 4 in your Moonbeam with it is cast.
Player3: shithead.
DM: Me?
Player1: Me?
Player2: Is it my turn now?
Since we're quoting XGtE...
Soo.. yeah, lines too.
Although, I do get what you're saying. If I'm casting a line spell that's supposed to be 5 feet wide, and I send it straight down the grid line from my corner, that's basically turning it into a line spell that's effectively 10 feet wide. Feels cheesy, but that does seem to be a valid usage. :/
You don't know what fear is until you've witnessed a drunk bird divebombing you while carrying a screaming Kobold throwing fire anywhere and everywhere.
Edit: Nevermind.