The behaviour of spells and/or line-effects when originating from larger creatures.
I have been looking around the internet and the sourcebooks in order to try to answer my question of how AoEs and Line effects behave when originating from Large, Huge, or Gargantuan creatures. I would deeply appreciate any feedback regarding the examples I present as well as guidance regarding how to use these effects correctly.
For demonstrational purposes, I will be using an Adult Blue Dragon's breathweapon, meaning it's a line with a width of 5ft.
I will be referencing rules for spells and their areas of effect since they're very similar to other AoE effects such as dragons' breathweapon.
The core rules for DND state the following regarding Line AoEs
Line
A line extends from its point of origin in a straight path up to its length and covers an area defined by its width.
A line's point of origin is not included in the line's area of effect, unless you decide otherwise.
Xanthar's also adds:
Lines.
A line can extend from its source orthogonally or diagonally, as shown in diagram 2.6.
In this case, the point of origin is the dragon, but what does that really mean?
What if the center of the token is the point of origin? That can't true though, since the description states that the point of origin isn't included in the effect's range, ruling it as originating from the center would mean that the larger a creature is, the shorter the effective area of its attack is, it would also mean that it's technically hitting itself each time it's using it's breathweapon. If this were true, Examples 1 & 3 would be correct while the others would be false.
What if the edge of the center-portion or the corner of the token is the point of origin, where the line is perpendicular to the face from which it originates? This statement seems plausible, it would mean the dragon isn't hitting itself and that its range isn't reduced due to its size. However, I can't seem to find any line of text that actually confirms this as true. If this were true, Examples 1 & 3 would be correct.
What if the edge of the token, at a spot of the dragon's choosing, is the point of origin, where the line is perpendicular to the face from which it originates? This scenario makes fora more agile and mobile dragon, being able to shoot lightning in three possible rows on each side of its token. The idea that a creature isn't exactly defined to only occupy the space in the center of its token is also supported by the rules of determining whether a creature has cover from a ranged attack. According to the "Cover rules", you draw imaginary line from one corner of the attacker's token (ergo the Point of Origin) to all corners of the victim's token. This reinforces and supports the idea that ranged attacks and possibly line effects can originate from widely different spots on the battlefields depending of the size of the attacker, since these imaginary lines are traced from an arbitrary, or the most convenient point. However, these rules only talk about the attack originating from different corners, which is close to but not precisely what our scenario described. If this were true, Examples 1, 2 and 3 would be correct.
Lastly, what if the edge of the token, at a spot of the dragon's choosing, is the point of origin, where the line's direction is arbitrary?
This would mean all examples would be correct, sine they all follow the rules of the scenario. At no point do the rules state a line effect such as a breathweapon must in a line perpendicular to face of the point of origin, they only state that Lines travel away from their point of origin in a straight line, which is true for all examples. At no point do the lines bend or change direction, which means it could be argued all examples are correct interpretations of the rules.
Now, I know some of these examples are more feasible than others, but I would still appreciate some guidance in what the rules say, both RAW and RAI. I am aware that the rules state the line travels orthogonally or straight, and that technically the dragon is the Point of Origin, but that still leaves things to interpret, meaning that perhaps all examples are correct, or maybe none are.
Thankyou for taking the time to respond, it really means a lot!
- A DM confused on how to run dragons and larger spellcaster.
An area of effect must be translated onto squares or hexes to determine which potential targets are in the area. If the area has a point of origin, choose an intersection of squares or hexes to be the point of origin, then follow its rules as normal. If an area of effect covers at least half a square or hex, the entire square or hex is affected.
For comparison, the 2014 DMG only mentioned circular AoEs: "If an area of effect is circular and covers at least half a square, it affects that square."
In my opinion, all your examples are correct because they follow the 2024 DMG rule I quoted and the 2024 Line AoE rule (note: I believe you quoted the 2014 Line AoE rule, but they're essentially the same)
Line [Area of Effect]
A Line is an area of effect that extends from a point of origin in a straight path along its length and covers an area defined by its width. The effect that creates a Line specifies its length and width.
A Line’s point of origin isn’t included in the area of effect unless its creator decides otherwise.
That said, the creature's size could affect Emanation AoE, but not Lines. I shared my opinion about that here:
I drew this picture for Spirit Guardians some time ago, to show how we play this kind of spell on a grid. Apart from the range (15 ft), I think it's the same idea now for Emanation AoE:
I draw more examples in the post Grid AoE Mechanics in case they’re useful for your future visitors.
The behaviour of spells and/or line-effects when originating from larger creatures.
I have been looking around the internet and the sourcebooks in order to try to answer my question of how AoEs and Line effects behave when originating from Large, Huge, or Gargantuan creatures. I would deeply appreciate any feedback regarding the examples I present as well as guidance regarding how to use these effects correctly.
For demonstrational purposes, I will be using an Adult Blue Dragon's breathweapon, meaning it's a line with a width of 5ft.
Example 1 - Straight, Center
Example 2 - Straight, Translated to the side
Example 3 - Diagonal, Top Right
Example 4 - Diagonal, Translated
Example 5 - Diagonal, Center
I will be referencing rules for spells and their areas of effect since they're very similar to other AoE effects such as dragons' breathweapon.
The core rules for DND state the following regarding Line AoEs
Xanthar's also adds:
In this case, the point of origin is the dragon, but what does that really mean?
What if the center of the token is the point of origin? That can't true though, since the description states that the point of origin isn't included in the effect's range, ruling it as originating from the center would mean that the larger a creature is, the shorter the effective area of its attack is, it would also mean that it's technically hitting itself each time it's using it's breathweapon. If this were true, Examples 1 & 3 would be correct while the others would be false.
What if the edge of the center-portion or the corner of the token is the point of origin, where the line is perpendicular to the face from which it originates? This statement seems plausible, it would mean the dragon isn't hitting itself and that its range isn't reduced due to its size. However, I can't seem to find any line of text that actually confirms this as true. If this were true, Examples 1 & 3 would be correct.
What if the edge of the token, at a spot of the dragon's choosing, is the point of origin, where the line is perpendicular to the face from which it originates? This scenario makes fora more agile and mobile dragon, being able to shoot lightning in three possible rows on each side of its token. The idea that a creature isn't exactly defined to only occupy the space in the center of its token is also supported by the rules of determining whether a creature has cover from a ranged attack. According to the "Cover rules", you draw imaginary line from one corner of the attacker's token (ergo the Point of Origin) to all corners of the victim's token. This reinforces and supports the idea that ranged attacks and possibly line effects can originate from widely different spots on the battlefields depending of the size of the attacker, since these imaginary lines are traced from an arbitrary, or the most convenient point. However, these rules only talk about the attack originating from different corners, which is close to but not precisely what our scenario described. If this were true, Examples 1, 2 and 3 would be correct.
Lastly, what if the edge of the token, at a spot of the dragon's choosing, is the point of origin, where the line's direction is arbitrary?
This would mean all examples would be correct, sine they all follow the rules of the scenario. At no point do the rules state a line effect such as a breathweapon must in a line perpendicular to face of the point of origin, they only state that Lines travel away from their point of origin in a straight line, which is true for all examples. At no point do the lines bend or change direction, which means it could be argued all examples are correct interpretations of the rules.
Now, I know some of these examples are more feasible than others, but I would still appreciate some guidance in what the rules say, both RAW and RAI. I am aware that the rules state the line travels orthogonally or straight, and that technically the dragon is the Point of Origin, but that still leaves things to interpret, meaning that perhaps all examples are correct, or maybe none are.
Thankyou for taking the time to respond, it really means a lot!
- A DM confused on how to run dragons and larger spellcaster.
Example 1: https://ibb.co/Br3WrYx
Example 2: https://ibb.co/LhwtsMb
Example 3: https://ibb.co/2k7T4xw
Example 4: https://ibb.co/6ghP8t1
Example 5: https://imgbb.com/C7jBgh1
The point of origin is the creature - i.e. any point within or on the edge of the space occupied by the creature.
I'd like to add some things from my side, if they help you @hajo07002 in some way.
First off, in the new DMG 2024, we have this rule, so it now includes all the Area of Effect shapes when using a grid.
For comparison, the 2014 DMG only mentioned circular AoEs: "If an area of effect is circular and covers at least half a square, it affects that square."
In my opinion, all your examples are correct because they follow the 2024 DMG rule I quoted and the 2024 Line AoE rule (note: I believe you quoted the 2014 Line AoE rule, but they're essentially the same)
That said, the creature's size could affect Emanation AoE, but not Lines. I shared my opinion about that here:
Thankyou so much! I've been trying to figure out which of the examples were correct, so this has been a great help!
Nah, it's a pleasure, friend!
I gathered some threads that might be useful for you. They were to me in the past: