Guys I am trying to get my rule right even when the DM isn’t in an AL game.
a dragon is doing a line attack on the ground. There are 3 pcs on a straight line on the ground at 20ft, 25ft and 30ft (they are in a straight line). So I have no issue with the dragon hitting all 3pcs. The 4th one is at 60ft up in the air because he can fly. The DM says the line attack still hits. I say that can’t be right because you can’t draw a straight line when there’s an angle involved. So if hit, it’s no longer a line attack but a vertical cone attack.
question is can a line attack be used as a vertical cone attack? I think not. In all honesty, if the DM can draw a line and hit all 4 in 3D, I will not argue with him but I know for a fact what he’s saying is impossible. You simply don’t travel in a straight horizontal line and then bends upwards at an angle and call that a straight line.
All line attacks have a width as well, if its 5' it would only hit people on the ground for instance and if it's 10' it would also hit the halfling standing on the halforcs shoulders.
But as Lyxen said, DM rulings are the rules. Part of the reason for this is to not have to stop the battle, look up rules, have a discussion, argue RAW vs RAI and so on, mid battle. The DM is the DM and could even argue that the dragons breath is a 120' radius from the dragon. Black dragons from the book do acid damage (i think) but the DM could decide all dragons do fire damage.
So, if the DM rules something, accept it and if you REALLY need to bring it up again or some reason, do it in a civil way after the game if you're calm, otherwise do it later (or, you know, just not at all).
As a Dm and being mean. I would say only 3 targets. Either the dragon hits 60 foot person if he is 60 feet down range and skips the 30 ft person. Or the dragon can only hit the three on the ground. And only if the line attack is 60 long.
As a person who says that a cone fired from the air hits the ground as a circle (ellipsoid), I have to also acknowledge that 60 feet in the air in not in line with grounded allies.
The Dragon was indeed a Blue Dragon. Thats why I have accepted the dragon's breath hit the 3 PCs on the ground. But then at an elevated angle after the third PC to catch the 4th PC who is 60ft above ground, I simply dont believe it can be regarded as a line. So if the DM insists on it (he is the person first breaking the rules), he should be questioned first whether he has made a mistake. Then he should confirm that he is breaking the rules. Third for fairness he should provide the players a chance to react to it. The fact the DM doesnt do all that and simply impose the results, the players will feel the DM is cheating ie. the DM is not trustworthy or he is railroading. Thats just not good for the game even cutting corners to some may be an ok thing to do.
The Dragon was indeed a Blue Dragon. Thats why I have accepted the dragon's breath hit the 3 PCs on the ground. But then at an elevated angle after the third PC to catch the 4th PC who is 60ft above ground, I simply dont believe it can be regarded as a line. So if the DM insists on it (he is the person first breaking the rules), he should be questioned first whether he has made a mistake. Then he should confirm that he is breaking the rules. Third for fairness he should provide the players a chance to react to it. The fact the DM doesnt do all that and simply impose the results, the players will feel the DM is cheating ie. the DM is not trustworthy or he is railroading. Thats just not good for the game even cutting corners to some may be an ok thing to do.
On the other hand perhaps it was the Xaniorific version of a blue dragon, namely the precise kind that lives in that world and THAT dragon in particular is known for it's sideways cone of breath. You don't know. It doesn't matter. DM can and should make quick rulings instead of stopping mid game to look up the rules.
I find it more disturbing that out of all the answers you got, where most were saying basically "don't argue with the dm, they can make these decisions for a reason" you chose one that confirmed what you wanted to get through, your version of it, making you right... And say the DM is cheating. The DM might not have gone by the monster manual, but on the other hand, he doesn't have to. I never even look in a monster manual when I make encounters, I just make my own monsters all the time. Changing stats or abilities is ok, for the DM.
Stopping the game to argue rules is not a good approach. Calling the DM a cheater is also not a good approach. Do you really imagine things will be good in any way doing this?
You should try to consider deeply what going this path is going to achieve, since you're clearly upset and seem to be aiming for a "Hah, I caught you cheating, you're a bad DM and you can't do that!" moment. Try to chill and instead be mature and let it go, or ask about it in a calm way AFTER the game, don't ruin stuff mid combat. Afterwards you could have said "Just for the record I thought a line is just a straight line, but it affects people above it as well? And does that tend to be the same for similar line effects, or was it more of a dragon thing?"
You're there to have fun, so is the DM and the rest of the party. Is it more important to be "right" than to have fun?
If the DM said "the dragon makes a line attack" and includes the flying party member, but doesn't allow players to do the same then that is a DM cheating his players. However, it's perfectly reasonable for the DM to say that this blue dragon's breath weapon isn't a line attack. When DM's don't play by the rules they set this is certainly "cheating" from the player perspective and is something all DMs should avoid.
Nuance, hard to tell in most cases since players and DMs sometimes have different ideas about what played out. DMs can cheat, they can also make mistakes and should look to rectify them once noticed.
Back to the original question. As far as I can tell there it does not say anywhere in the rules how high a line attack is. It is 90 ft long (for an adult) and 5 foot wide but I can not find anywhere that says how high it is.
I would rule that it is also 5 foot high so the flying PC can not be hit as well as the two characters on the ground but it is not against RAW to say it is a 90 ft high (or even more) in which case the flying PC could be hit.
As I made clear in my post, there is nuance involved. DMs are allowed to make mistakes, your examples are all ways to rectify it once you pointed it out. You are directly agreeing what what I said but assuming I said "REVERSE EVERYTHING" or "ARGUE ARGUE ARGUE". OP said "line" multiple times, not "x, y and z are hit" hence me saying that if a DM is interpreting line in this way, they should allow their players to do the same. The likelihood is that he made a quick decision and made a mistake he can avoid in the future, but its not always the case.
However, you forget that some DMs have DM v Player mentality and bend the rules they set to suit them and not their players. DMs are not infallible, some are bad, some cheat.
Please try not to defensively multi-quote someone just to make yourself feel better, at least try to read their post without picking apart every syllable to suit your agenda. :)
RE: Dimensions, the diagram for line AOEs in the PHB shows a 2D line, rather than a 3D shape like the others. I would say assuming the height=width is the nicest way of resolving the size of the beam.
A line attack is like a laser beam attack. It simply doesnt zigzag. See p87 of XGE. If there is a rule which is stated clearly in the book which requires no interpretation then any misinterpretation is defacto changing the rule. What do you call a person who changes the rules of a game in the middle of the game to suit his needs? A cheater.
A line attack is like a laser beam attack. It simply doesnt zigzag. See p87 of XGE. If there is a rule which is stated clearly in the book which requires no interpretation then any misinterpretation is defacto changing the rule. What do you call a person who changes the rules of a game in the middle of the game to suit his needs? A cheater.
It must be very important for you to be right?
Nothing in the rules, neither PHB or Xgte specifices any HEIGHT of a line, it just has examples of what direction it goes. This means technically it's a DM's call, which it was anyways. Like it has been stated before, the line is most likely the way you describe it but it doesn't mean you have the right to ruin the game by stopping the battle, arguing and making a scene about you instead of the game. That's exactly why the rule of the DM making the calls is there. In addition, monsters DON'T go by the same rules as players, so it wouldn't matter anyways. Monsters can have better or worse stats, higher limits on attributes, powers players cannot have and so on.
You even got good examples of how to bring it up, but your solution seems to be to... Just call them cheater and be angry about it. I'm not quite sure why even asked about it here since clearly you already made up your mind.
I'm not sure but I get the impression that you're very young so I will drop this discussion now, I hope your attitude doesn't get you thrown out of the game because it sure would at my table, you're the very definition of a toxic player as you portray yourself here. Good luck mate.
Who is ruining the game in the first place? Of course is the cheater. Cheaters are the ones that are toxic. You wont call any law abiding citizens to be toxic. So this is just plainly wrong. If you like being cheated then tell you what nothing to stop a DM who feels like it to say you die even though you do not get hit and he simply wants to see you losing everything. This is what is going to happen if you dont stop DM cheating.
Also, you guys assume the DM is noble and hence you think he is doing it for the good of the game. But what if he is not noble. He simply does it as a revenge against you. I have seen such DM in action. And that ruins the game for everyone. After that, we have all agreed that we do not allow DM cheating. If a DM does change the rule in the middle of the game, the players are allowed to have a free round because it is only fair that the players are allowed to reposition or do something to avoid getting unfairly treated. Yes, thats not in the rule but we all made it as a rule because a game needs to have rules to play. Rules need to be agreed by everyone playing it. Rules cant be arbitrary. Thats the way it should be. Just stating that DM can do anything is a problem. Allowing the DM to cheat is also a problem. Telling me who is the one fixing the problem is also a problem. I am the one who is doing something rather than someone yelling at me giving me names. Shame on you.
Asserting the DM can't cheat is semantics. What it comes down to is the term line is defined by the rules, which is a contract between the DM and players regarding how the world works. Line is shorthand for a type of attack that behaves a certain way. When players can't rely on basic terms being respected, they can't make informed decisions about how to counter or defend against such attacks.
A line extends from its point of origin in a straight path up to its length and covers an area defined by its width.
Game terms exist so that players can make choices that matter. If they know they're fighting a blue dragon, they may very well plan to avoid standing in a line because of the nature of the dragon's breath. When they then get hit with "actually, it hits you anyway," it teaches the players to stop trying to use monster knowledge or tactics because the DM is just going to narrate whatever results they want during combat. It erodes the trust between DM and players and poisons the game.
Now if you want to redefine what line means in your game and apply that everywhere, that's cool. Or if you want to say this dragon has a special kind of breath, that's fine too. But don't make it up on the spot just so you can hit everyone. It's cheap and everyone at the table knows you're bending the rules to get the outcome you want regardless of what the players do.
Nothing in the rules, neither PHB or Xgte specifices any HEIGHT of a line, it just has examples of what direction it goes.
See my quote above from the PHB. It is accompanied by a picture of a line as well, next to 3-D depictions of other area types. A line is a line. That's why they call it a line.
Also, you guys assume the DM is noble and hence you think he is doing it for the good of the game. But what if he is not noble. He simply does it as a revenge against you. I have seen such DM in action. And that ruins the game for everyone. After that, we have all agreed that we do not allow DM cheating. If a DM does change the rule in the middle of the game, the players are allowed to have a free round because it is only fair that the players are allowed to reposition or do something to avoid getting unfairly treated. Yes, thats not in the rule but we all made it as a rule because a game needs to have rules to play. Rules need to be agreed by everyone playing it. Rules cant be arbitrary. Thats the way it should be. Just stating that DM can do anything is a problem. Allowing the DM to cheat is also a problem. Telling me who is the one fixing the problem is also a problem. I am the one who is doing something rather than someone yelling at me giving me names. Shame on you.
But you're the one saying the DM is a cheater, that's the same. That's the point I was trying to make and if you got offended that's a shame but it wasn't my intention. What I wanted you to see was that your behavior will only make things worse. You're upset and seemingly pretty agitated. Going into a discussion with your DM in this state will not solve the situation, it will escalate the situation.
Of course there are people who will abuse the rules, but that's a whole other discussion. The DM CAN and SHOULD make decisions to stop the game from coming to a halt for a discussion. This doesn't mean it's "ok" to behave badly.
Me, as the DM, in this situation would have let the flyer be safe. But this DM didn't. Calling them a cheater does NOT make things better, this is NOT you "fixing" the situation, this is you escalating the situation. Which is why me and others said you should talk about it in a calm way if you do bring it up. Being upset and calling someone a cheater is not being calm.
If you have a DM that's really just "out to get you" why are you playing with them? I have had those kind of DM's myself, I know it sucks. But I mean, either you're friends, in this case you should be able to talk about it without becoming enemies, or it's someone who isn't a friend so... Maybe start a group without them? Might not always be that easy but worth considering.
Now, I'm out of the thread, sorry if you felt targeted, chill out.. it's supposed to be fun :)
D&D is not players vs DM, the DM is the storyteller and arbiter of the rules. If it was players v DM tyhe DM would win every time by putting theem against overwhelmingly powerful monsters or laying a trap that contains 9th level fireball which has a DC80 to spot it,
In my experiance most DM cheating is in favor of the players:
DM says : The veteran sees the wizard who paralyzed him at the big threat and runs to him and makes two attacks with his longsword and 1 with his shortsword against him...1st attack is a critical hit for 18 damage the second.... Wizard says: I'm down DM thinks: Oh **** I didn't realise he had so much damage they don't have revivify but at least it is the cleric's turn next so he should get healed or at least stabalised before his next turn DM says: Second attack is a hit so that is two failed death saves DM thinks: I don't want to kill off the wizard when the party could do nothing about it regardless what I roll I will say it is a miss so the cleric can save him.
And the DM is perfectly fine to change whatever he wants in the way the breath weapons behave to surprise the players and avoid their metagaming about things that they should not know about. If the DM wants to have a blue dragon that breathes a cone, it's fine. If the DM wants the breath weapon to behave like Chain Lighting, jumping from one target to the next, that's how it works.
The players should only be able to make informed decisions about what their characters know, not what the players have read in the rules or the monster manual, that's metagaming and actually cheating much more than any DM could.
I've actually run a session where my blue dragon's lightning breath working like a chain lightning spell, where the bolt started as a line and then jumped to multiple targets after the first impact. Players actually received some hints about this change prior to the final confrontation, but they didn't really focus on some of the hints that I was dropping. They were so caught up on what they expected it to be that they didn't consider that something might be different.
To paraphrase a moment from that encounter:
Players: What the heck just happened? How did it do that?
DM (me): Bard give me an Intelligence check.
Player (bard): *rolls die* I got a 17.
DM (me): Okay, you recall that while you were gathering information about the dragon in the nearby town there were rumors about the dragon studying the arcane arts as well as spending time kidnapping some notable wizards. It would seem that the dragon's studies were not just a matter of learning how to cast spells, but it would seem that it also found a way to augment the elemental nature of its breath.
Players: Oh, man! This just got a lot more interesting.
Now, I'll admit what I did was probably different than the situation that the OP is presenting. I had the dragon variant designed in advance with notes indicating the "chain lightning" breath attack. I also gave some clues leading up to the battle that the dragon would have some differences than the normal blue dragon type. Not saying that the OP's DM is either right or wrong in how he handled their situation, but I can understand where confusion and frustration can arise when something completely unexpected suddenly occurs.
This thread is not the place to debate the nuances and remits of the Dungeon Master, it's a question on how to rule line breath attacks. Please keep things on topic.
Regarding the topic of line areas for spells and other effects, the Basic Rules says the following:
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.
It's important to note the line "covers an area defined by its width"; this would indicate it cannot affect creatures more than half the width from the path the line traces.
Guys I am trying to get my rule right even when the DM isn’t in an AL game.
a dragon is doing a line attack on the ground. There are 3 pcs on a straight line on the ground at 20ft, 25ft and 30ft (they are in a straight line). So I have no issue with the dragon hitting all 3pcs. The 4th one is at 60ft up in the air because he can fly. The DM says the line attack still hits. I say that can’t be right because you can’t draw a straight line when there’s an angle involved. So if hit, it’s no longer a line attack but a vertical cone attack.
question is can a line attack be used as a vertical cone attack? I think not. In all honesty, if the DM can draw a line and hit all 4 in 3D, I will not argue with him but I know for a fact what he’s saying is impossible. You simply don’t travel in a straight horizontal line and then bends upwards at an angle and call that a straight line.
All line attacks have a width as well, if its 5' it would only hit people on the ground for instance and if it's 10' it would also hit the halfling standing on the halforcs shoulders.
But as Lyxen said, DM rulings are the rules. Part of the reason for this is to not have to stop the battle, look up rules, have a discussion, argue RAW vs RAI and so on, mid battle. The DM is the DM and could even argue that the dragons breath is a 120' radius from the dragon. Black dragons from the book do acid damage (i think) but the DM could decide all dragons do fire damage.
So, if the DM rules something, accept it and if you REALLY need to bring it up again or some reason, do it in a civil way after the game if you're calm, otherwise do it later (or, you know, just not at all).
Have fun :)
As a Dm and being mean. I would say only 3 targets. Either the dragon hits 60 foot person if he is 60 feet down range and skips the 30 ft person. Or the dragon can only hit the three on the ground. And only if the line attack is 60 long.
No Gaming is Better than Bad Gaming.
As a person who says that a cone fired from the air hits the ground as a circle (ellipsoid), I have to also acknowledge that 60 feet in the air in not in line with grounded allies.
The (line) breath weapon of an Adult Blue Dragon is essentially a 5ft diameter cylinder that extends from the dragon.
The Dragon was indeed a Blue Dragon. Thats why I have accepted the dragon's breath hit the 3 PCs on the ground. But then at an elevated angle after the third PC to catch the 4th PC who is 60ft above ground, I simply dont believe it can be regarded as a line. So if the DM insists on it (he is the person first breaking the rules), he should be questioned first whether he has made a mistake. Then he should confirm that he is breaking the rules. Third for fairness he should provide the players a chance to react to it. The fact the DM doesnt do all that and simply impose the results, the players will feel the DM is cheating ie. the DM is not trustworthy or he is railroading. Thats just not good for the game even cutting corners to some may be an ok thing to do.
On the other hand perhaps it was the Xaniorific version of a blue dragon, namely the precise kind that lives in that world and THAT dragon in particular is known for it's sideways cone of breath. You don't know. It doesn't matter. DM can and should make quick rulings instead of stopping mid game to look up the rules.
I find it more disturbing that out of all the answers you got, where most were saying basically "don't argue with the dm, they can make these decisions for a reason" you chose one that confirmed what you wanted to get through, your version of it, making you right... And say the DM is cheating. The DM might not have gone by the monster manual, but on the other hand, he doesn't have to. I never even look in a monster manual when I make encounters, I just make my own monsters all the time. Changing stats or abilities is ok, for the DM.
Stopping the game to argue rules is not a good approach. Calling the DM a cheater is also not a good approach. Do you really imagine things will be good in any way doing this?
You should try to consider deeply what going this path is going to achieve, since you're clearly upset and seem to be aiming for a "Hah, I caught you cheating, you're a bad DM and you can't do that!" moment. Try to chill and instead be mature and let it go, or ask about it in a calm way AFTER the game, don't ruin stuff mid combat. Afterwards you could have said "Just for the record I thought a line is just a straight line, but it affects people above it as well? And does that tend to be the same for similar line effects, or was it more of a dragon thing?"
You're there to have fun, so is the DM and the rest of the party. Is it more important to be "right" than to have fun?
DM's can absolutely cheat, bad take.
If the DM said "the dragon makes a line attack" and includes the flying party member, but doesn't allow players to do the same then that is a DM cheating his players. However, it's perfectly reasonable for the DM to say that this blue dragon's breath weapon isn't a line attack. When DM's don't play by the rules they set this is certainly "cheating" from the player perspective and is something all DMs should avoid.
Nuance, hard to tell in most cases since players and DMs sometimes have different ideas about what played out. DMs can cheat, they can also make mistakes and should look to rectify them once noticed.
Back to the original question. As far as I can tell there it does not say anywhere in the rules how high a line attack is. It is 90 ft long (for an adult) and 5 foot wide but I can not find anywhere that says how high it is.
I would rule that it is also 5 foot high so the flying PC can not be hit as well as the two characters on the ground but it is not against RAW to say it is a 90 ft high (or even more) in which case the flying PC could be hit.
As I made clear in my post, there is nuance involved. DMs are allowed to make mistakes, your examples are all ways to rectify it once you pointed it out. You are directly agreeing what what I said but assuming I said "REVERSE EVERYTHING" or "ARGUE ARGUE ARGUE". OP said "line" multiple times, not "x, y and z are hit" hence me saying that if a DM is interpreting line in this way, they should allow their players to do the same. The likelihood is that he made a quick decision and made a mistake he can avoid in the future, but its not always the case.
However, you forget that some DMs have DM v Player mentality and bend the rules they set to suit them and not their players. DMs are not infallible, some are bad, some cheat.
Please try not to defensively multi-quote someone just to make yourself feel better, at least try to read their post without picking apart every syllable to suit your agenda. :)
RE: Dimensions, the diagram for line AOEs in the PHB shows a 2D line, rather than a 3D shape like the others. I would say assuming the height=width is the nicest way of resolving the size of the beam.
A line attack is like a laser beam attack. It simply doesnt zigzag. See p87 of XGE. If there is a rule which is stated clearly in the book which requires no interpretation then any misinterpretation is defacto changing the rule. What do you call a person who changes the rules of a game in the middle of the game to suit his needs? A cheater.
It must be very important for you to be right?
Nothing in the rules, neither PHB or Xgte specifices any HEIGHT of a line, it just has examples of what direction it goes. This means technically it's a DM's call, which it was anyways. Like it has been stated before, the line is most likely the way you describe it but it doesn't mean you have the right to ruin the game by stopping the battle, arguing and making a scene about you instead of the game. That's exactly why the rule of the DM making the calls is there. In addition, monsters DON'T go by the same rules as players, so it wouldn't matter anyways. Monsters can have better or worse stats, higher limits on attributes, powers players cannot have and so on.
You even got good examples of how to bring it up, but your solution seems to be to... Just call them cheater and be angry about it. I'm not quite sure why even asked about it here since clearly you already made up your mind.
I'm not sure but I get the impression that you're very young so I will drop this discussion now, I hope your attitude doesn't get you thrown out of the game because it sure would at my table, you're the very definition of a toxic player as you portray yourself here. Good luck mate.
Who is ruining the game in the first place? Of course is the cheater. Cheaters are the ones that are toxic. You wont call any law abiding citizens to be toxic. So this is just plainly wrong. If you like being cheated then tell you what nothing to stop a DM who feels like it to say you die even though you do not get hit and he simply wants to see you losing everything. This is what is going to happen if you dont stop DM cheating.
Also, you guys assume the DM is noble and hence you think he is doing it for the good of the game. But what if he is not noble. He simply does it as a revenge against you. I have seen such DM in action. And that ruins the game for everyone. After that, we have all agreed that we do not allow DM cheating. If a DM does change the rule in the middle of the game, the players are allowed to have a free round because it is only fair that the players are allowed to reposition or do something to avoid getting unfairly treated. Yes, thats not in the rule but we all made it as a rule because a game needs to have rules to play. Rules need to be agreed by everyone playing it. Rules cant be arbitrary. Thats the way it should be. Just stating that DM can do anything is a problem. Allowing the DM to cheat is also a problem. Telling me who is the one fixing the problem is also a problem. I am the one who is doing something rather than someone yelling at me giving me names. Shame on you.
Asserting the DM can't cheat is semantics. What it comes down to is the term line is defined by the rules, which is a contract between the DM and players regarding how the world works. Line is shorthand for a type of attack that behaves a certain way. When players can't rely on basic terms being respected, they can't make informed decisions about how to counter or defend against such attacks.
Game terms exist so that players can make choices that matter. If they know they're fighting a blue dragon, they may very well plan to avoid standing in a line because of the nature of the dragon's breath. When they then get hit with "actually, it hits you anyway," it teaches the players to stop trying to use monster knowledge or tactics because the DM is just going to narrate whatever results they want during combat. It erodes the trust between DM and players and poisons the game.
Now if you want to redefine what line means in your game and apply that everywhere, that's cool. Or if you want to say this dragon has a special kind of breath, that's fine too. But don't make it up on the spot just so you can hit everyone. It's cheap and everyone at the table knows you're bending the rules to get the outcome you want regardless of what the players do.
TLDR it's a violation of the social contract.
My homebrew subclasses (full list here)
(Artificer) Swordmage | Glasswright | (Barbarian) Path of the Savage Embrace
(Bard) College of Dance | (Fighter) Warlord | Cannoneer
(Monk) Way of the Elements | (Ranger) Blade Dancer
(Rogue) DaggerMaster | Inquisitor | (Sorcerer) Riftwalker | Spellfist
(Warlock) The Swarm
See my quote above from the PHB. It is accompanied by a picture of a line as well, next to 3-D depictions of other area types. A line is a line. That's why they call it a line.
My homebrew subclasses (full list here)
(Artificer) Swordmage | Glasswright | (Barbarian) Path of the Savage Embrace
(Bard) College of Dance | (Fighter) Warlord | Cannoneer
(Monk) Way of the Elements | (Ranger) Blade Dancer
(Rogue) DaggerMaster | Inquisitor | (Sorcerer) Riftwalker | Spellfist
(Warlock) The Swarm
But you're the one saying the DM is a cheater, that's the same. That's the point I was trying to make and if you got offended that's a shame but it wasn't my intention. What I wanted you to see was that your behavior will only make things worse. You're upset and seemingly pretty agitated. Going into a discussion with your DM in this state will not solve the situation, it will escalate the situation.
Of course there are people who will abuse the rules, but that's a whole other discussion. The DM CAN and SHOULD make decisions to stop the game from coming to a halt for a discussion. This doesn't mean it's "ok" to behave badly.
Me, as the DM, in this situation would have let the flyer be safe. But this DM didn't. Calling them a cheater does NOT make things better, this is NOT you "fixing" the situation, this is you escalating the situation. Which is why me and others said you should talk about it in a calm way if you do bring it up. Being upset and calling someone a cheater is not being calm.
If you have a DM that's really just "out to get you" why are you playing with them? I have had those kind of DM's myself, I know it sucks. But I mean, either you're friends, in this case you should be able to talk about it without becoming enemies, or it's someone who isn't a friend so... Maybe start a group without them? Might not always be that easy but worth considering.
Now, I'm out of the thread, sorry if you felt targeted, chill out.. it's supposed to be fun :)
D&D is not players vs DM, the DM is the storyteller and arbiter of the rules. If it was players v DM tyhe DM would win every time by putting theem against overwhelmingly powerful monsters or laying a trap that contains 9th level fireball which has a DC80 to spot it,
In my experiance most DM cheating is in favor of the players:
DM says : The veteran sees the wizard who paralyzed him at the big threat and runs to him and makes two attacks with his longsword and 1 with his shortsword against him...1st attack is a critical hit for 18 damage the second....
Wizard says: I'm down
DM thinks: Oh **** I didn't realise he had so much damage they don't have revivify but at least it is the cleric's turn next so he should get healed or at least stabalised before his next turn
DM says: Second attack is a hit so that is two failed death saves
DM thinks: I don't want to kill off the wizard when the party could do nothing about it regardless what I roll I will say it is a miss so the cleric can save him.
I've actually run a session where my blue dragon's lightning breath working like a chain lightning spell, where the bolt started as a line and then jumped to multiple targets after the first impact. Players actually received some hints about this change prior to the final confrontation, but they didn't really focus on some of the hints that I was dropping. They were so caught up on what they expected it to be that they didn't consider that something might be different.
To paraphrase a moment from that encounter:
Now, I'll admit what I did was probably different than the situation that the OP is presenting. I had the dragon variant designed in advance with notes indicating the "chain lightning" breath attack. I also gave some clues leading up to the battle that the dragon would have some differences than the normal blue dragon type. Not saying that the OP's DM is either right or wrong in how he handled their situation, but I can understand where confusion and frustration can arise when something completely unexpected suddenly occurs.
This thread is not the place to debate the nuances and remits of the Dungeon Master, it's a question on how to rule line breath attacks. Please keep things on topic.
Regarding the topic of line areas for spells and other effects, the Basic Rules says the following:
It's important to note the line "covers an area defined by its width"; this would indicate it cannot affect creatures more than half the width from the path the line traces.
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