Temp hp and Concentration checks

[Sparky McDibben]

Does losing Temp hp only (and not regular hp) trigger a concentration check? This might be a stupid question, but screw it, I need to know.

[Wizard_Lizard]

that's... ...a good question...
I would have assumed that it does, but now the alternative seems... ...intriguing...

[Sparky McDibben]

So, per PHB, p 203, a concentration check is triggered by "taking damage."

Per PHB, p 198, temporary hit points are "a buffer against damage, a pool of hit points that protect you from injury."

Sooo.... yeah. I would say that if you don't lose actual hp, you don't have to make a concentration check.

[KorvinStarmast]

Does losing Temp hp only (and not regular hp) trigger a concentration check? This might be a stupid question, but screw it, I need to know. Nope ... at least at our table we don't do it that way.

But, if you abide by the official 2019 WoTC Sage Advice Compendium rulings ...


If I have 10 temporary hit points and I take 30 damage from an attack while concentrating on a spell, what is the DC of the Constitution save to maintain my concentration?

The DC is 15 in that case. When temporary hit points absorb damage for you, you’re still taking damage, just not to your real hit points. In contrast, a feature like the wizard’s Arcane Ward can take damage for you, potentially eliminating the need to make a Constitution saving throw or, at least, lowering the DC of that save. This would appear to support Sparky's point in his post.

So, pick what works best at your table.

[EggKookoo]

I vote yes, you make a check. Hit points are an abstraction. Temporary hit points doubly so.

[Contrast]

This would appear to support Sparky's point in his post.

No it doesn't? Concentration checks are triggered by taking damage. Damage absorbed by THP is still taking damage (as the Sage Advice specifically highlights) and therefore triggers a concentration check.

If THP didn't count as 'taking damage' the answer given by the SA Compendium would have been DC10 not DC15.

[EggKookoo]

Also, isn't it also RAW that if you have damage resistance, that's applied first, then temp hp are reduced? That would suggest temp hp aren't really separate from you. It's just a rule mechanic to apply a little extra survivability, or to imply your current state of extra-survivability is transitory. Temp hp aren't literally like a force field (unless they're being provided by an actual force field, I suppose).

[JackPhoenix]

Also, isn't it also RAW that if you have damage resistance, that's applied first, then temp hp are reduced? That would suggest temp hp aren't really separate from you. It's just a rule mechanic to apply a little extra survivability, or to imply your current state of extra-survivability is transitory. Temp hp aren't literally like a force field (unless they're being provided by an actual force field, I suppose).

That's relevant for abjurer's Arcane Ward: unlike temporary HP, wizard's damage reduction does not apply to the ward.

[Tanarii]

But, if you abide by the official 2019 WoTC Sage Advice Compendium rulings ...
That seems weird. If they're buffering you against damage, it feels like they should reduce the DC of a concentration check.

Based entirely on a gut feeling off the cuff. :smallamused:

[Contrast]

That seems weird. If they're buffering you against damage, it feels like they should reduce the DC of a concentration check.

Based entirely on a gut feeling off the cuff. :smallamused:

By that logic Aid should also help but also doesn't.

It makes sense to me - THP (and Aid) keep you on your feet longer but they're not actually stopping you taking the hits. You're still taking the full force of the blows and in this case its the force of the blows that is the issue.

Edit - It's also worth saying, as someone playing a glamour bard this would be a pretty major buff to THP and make glamour bards and Inspiring Leader (which I would argue are already very good) very very attractive.

[diplomancer]

Concentration check for damage is because you just got a big hit. The bigger the hit, the greater the difficulty of maintaining it.

Why would a character with 50 HPs and 50 THPs take 50 points of damage and not make a concentration check, when a character with 100 HPs and no THPs has to make a DC25 check for that same damage? They both got walloped equally, and they are both at the same amount of HPs.

[JNAProductions]

Depends on the source of THP, to me.

Heroism THP wouldn't stop a Concentration check, since it's THP from motivation.
Armor of Agathys would, since it's a physical (well, semi-physical) barrier from harm.

Edit: I freely admit this is not RAW in the slightest, but makes sense to me.

[Bjarkmundur]

Depends on the source of THP, to me.

Heroism THP wouldn't stop a Concentration check, since it's THP from motivation.
Armor of Agathys would, since it's a physical (well, semi-physical) barrier from harm.

Edit: I freely admit this is not RAW in the slightest, but makes sense to me.


So, pick what works best at your table.
^agree


Sage Advice has always felt weird to me. I am personally under the impression that a lot of the vagueness of 5e is deliberately designed to move power over the the DM, giving him more freedom to rule in the favor of fun.

[Tanarii]

By that logic Aid should also help but also doesn't. Aid gives actual hit points, so it does not follow. In fact, Aid as a counter-example just reinforces my gut feeling.

I clearly pointed out its not "logic" :smalltongue:
Except in the common Internet usage of the term.

[EggKookoo]

I am personally under the impression that a lot of the vagueness of 5e is deliberately designed to move power over the the DM, giving him more freedom to rule in the favor of fun.

I feel like this was explicitly stated by the devs at some point. But even if it wasn't, it's the obvious implication of the rules (at least to me).

[RSP]

RAW, I’d say the “buffer against damage” is relevant, while the SAC is clear as well, if you choose to go by that.

Personally, I try to imagine the in-game perspective on these types of questions. For instance, if a PC has 5 tHP and full HP, and an attack deals 5 damage; leaving the PC with full HPs, has that character actually taken damage?

I’d say no, due to the PC being at full health and there being nothing to heal; but other tables may see that answer differently.

[EggKookoo]

RAW, I’d say the “buffer against damage” is relevant, while the SAC is clear as well, if you choose to go by that.

Personally, I try to imagine the in-game perspective on these types of questions. For instance, if a PC has 5 tHP and full HP, and an attack deals 5 damage; leaving the PC with full HPs, has that character actually taken damage?

I’d say no, due to the PC being at full health and there being nothing to heal; but other tables may see that answer differently.

Right. For me, hit points don't correlate to anything extant in the fiction but are just a UI tool to help the game function as a game for the players. So temp hp are just "more hp."

But even from your point of view, you could easily say the character was also at full health with full hp + 5 thp. It's just that their health was "fuller," so to speak. It's really no weirder than a character at full health gaining a level and then gaining another HD worth of hit points. If the character was at full health just before leveling, where are they afterward? If they're at full health after leveling, were they somehow less than full health before? Temp hp just raises the value for what "full health" means, albeit temporarily.

[RSP]

But even from your point of view, you could easily say the character was also at full health with full hp + 5 thp.

I don’t believe so. It’s a question of whether something is damaged or not. From my perspective, 80/80 HP is undamaged and there is nothing to heal. 80/80 with tHP is also undamaged. However, if that character takes 5 damage, how are they both undamaged and damaged? It’s not possible, therefore, as I see it, tHP aren’t possibly “just more HPs.” This is backed up by the RAW of tHP being a “buffer” against damage: that is, whatever the source of the tHP is, is what took the damage; not the body of the character.

In this light, the character did not take damage because a thing cannot both take damage and be undamaged, without something else occurring to fix or heal that damage, such as how a troll regenerates.

[EggKookoo]

I don’t believe so. It’s a question of whether something is damaged or not. From my perspective, 80/80 HP is undamaged and there is nothing to heal. 80/80 with tHP is also undamaged. However, if that character takes 5 damage, how are they both undamaged and damaged? It’s not possible, therefore, as I see it, tHP aren’t possibly “just more HPs.” This is backed up by the RAW of tHP being a “buffer” against damage: that is, whatever the source of the tHP is, is what took the damage; not the body of the character.

Which of course conflicts with the notion that you apply damage resistance before deducting temp hp. If temp hp is some kind of pre-damage buffer, your damage resistance shouldn't affect it.

[RSP]

Which of course conflicts with the notion that you apply damage resistance before deducting temp hp. If temp hp is some kind of pre-damage buffer, your damage resistance shouldn't affect it.

I don’t necessarily agree with that. There’s plenty of ways you could have resistance that would make sense to affect tHP.

Again, explaining how getting damaged by a knife attack, but not being damaged, is a lot harder to explain, logically.

[Spiritchaser]

Interesting. I’d just always assumed it provided a buffer because it prevented damage to HP.

I certainly wouldn’t change anything in progress, but I’ll have to sort out what to do before I start another campaign.

For what it’s worth, I don’t think using it as a buffer has broken anything, although removing that property will make heroism (and similar effects) less useful to casters.

That being said, it usually doesn’t change things a whole lot.

[EggKookoo]

Again, explaining how getting damaged by a knife attack, but not being damaged, is a lot harder to explain, logically.

Yes, if you view hit points as discrete things that somehow exist within the fiction. Which is one reason I don't -- in my games hit points are as tangible as, say, your Proficiency Bonus, so it's not as much of a problem and RAW temp hp make sense as "more hp."

[KorvinStarmast]

No it doesn't? Hmmmm, I appear to have misread Sparky's post, since I took the yeah to mean that it forces the con check ... but I guess I misread his post, now that I go back and look.

[Contrast]

Aid gives actual hit points, so it does not follow. In fact, Aid as a counter-example just reinforces my gut feeling.

I clearly pointed out its not "logic" :smalltongue:
Except in the common Internet usage of the term.

The argument was that because THP are described as 'a buffer against damage' they should be treated differently than HP. Aid is described that it 'bolsters your allies with toughness and resolve'.

It's bolstering toughness and mental fortitude, surely that should give you some benefit on a test constitution save to maintain concentration due to blows? Advantage would be reasonable surely? I know it doesn't say you get that but the game empowers DMs to make calls that make sense...

There's a slippery slope with trying to argue descriptions into mechanical benefits they don't outline and THP making you immune to concentration (and presumably other on damage effects like poisons?) is a step too far for me. Many people don't even necessarily describe every hit that does HP damage as an actually wounding blow anyway. In that case trying to rule on differences in mechanical effect on fluff justification becomes even more iffy.

For me at least its a triple whammy of being officially wrong, doesn't make as much sense as the alternative (to me at least - I was honestly surprised to see so much support for it in this thread) and buffs something that I don't think needs buffing.

[RSP]

Yes, if you view hit points as discrete things that somehow exist within the fiction. Which is one reason I don't -- in my games hit points are as tangible as, say, your Proficiency Bonus, so it's not as much of a problem and RAW temp hp make sense as "more hp."

No. I’m not sure why you think I need to see tHPs how you think I should, or why you’ve decided multiple times to try and explain my view, but you’re doing a poor job of it.

You don’t have to view HPs as “discrete things” that exist in-game, to see an issue with explaining how something can be damaged and undamaged at the same time. Either something has taken damage, or it hasn’t.

Either a knife attack damages a character, or it doesn’t. If it damages a character, then that character cannot also be undamaged (again, unless something else fixes the damaged in its entirety). If in your game you want to describe a damaging attack as one that almost hits, but doesn’t, cool. But that’s still then damage done to a character, and it makes no sense to then also describe that character as “undamaged.” I also find that to be a difficult way to differentiate between “healable damage” and “non-healable damage” in that some misses will just be misses, some misses will be missed that do damage and require healing and some misses will do damage and not require healing. I also find issues with why anyone would waste magic to “heal” someone who isn’t actually hurt (but has just lost their “luck points”), but we’re getting off topic.

However you want to describe taking damage, then that means there’s an inconsistent when describing something that takes damage as being undamaged.

[strangebloke]

Very little to say here that hasn't already been said, but yeah.

RAW is unclear. Sage Advice says yes you make a check.

In actual play, most forms of THP are morale bonuses, so you should have to make a check since its not really any difference from the rest of your HP. Other forms are more solid, and you might not make a check. Armor of Agathys is one example, but there's an even more extreme one:

Tomb of Levistus.

You're covered in Ice so thick you can tank five castings of disintegrate but if a Kobold comes up and whacks your icy tomb with a stick, you better make a DC 10 concentration check.

Play it by ear and make it up as you go, life is short and you'll be happier in the end if you don't fret over questions like this.

[RSP]

There's a slippery slope with trying to argue descriptions into mechanical benefits they don't outline and THP making you immune to concentration (and presumably other on damage effects like poisons?) is a step too far for me. Many people don't even necessarily describe every hit that does HP damage as an actually wounding blow anyway. In that case trying to rule on differences in mechanical effect on fluff justification becomes even more iffy.

First off, I agree the implications of playing tHP as RAW states (“a buffer”) has significant changes, and I’m not saying that’s how they should be played. AoA becomes a much more effective spell, for instance. And yes, you can get into some interesting questions of whether additional effects would activate to further increase the effectiveness of using tHP (though the official rules already allow this with Abjurer’s Ward so it’s not necessarily game breaking or something outside what the game officially allows)

However, the RAW states “Whenever a creature takes damage, that damage is subtracted from its hit points” and “Temporary hit points aren’t actual hit points; they are a buffer against damage, a pool of hit points that protect you from injury.” RAW, tHP prevent the character from actually taking damage.

This should probably be errata’d as i imagine it’s one of the cases where the writers used a word (in this case “damage”) both as its common English meaning and as it’s game specific meaning (that is, damage=HP loss) without differentiating between the two.



For me at least its a triple whammy of being officially wrong, doesn't make as much sense as the alternative (to me at least - I was honestly surprised to see so much support for it in this thread) and buffs something that I don't think needs buffing.

I think the buff is the main issue. I disagree on counting tHP as taking damage as making sense in-game: if your tHP are “a protective magical force...manifesting as a spectral frost that covers you and your gear,” why then are you “taking damage” when a dagger only scrapes the frost, neither penetrating the protective magic force nor even touching the character’s body? Nothing actually caused HP loss to the character (that is, damaged them), so why then, are they considered to have taken damage?

Ultimately, though, I agree tHP cause issues if played as anything other than “additional, non-recoverable HPs”, and as such would suggest its easier to play them that way. I just disagree that viewing tHP that way in-game makes sense.

[RSP]

Tomb of Levistus.

You're covered in Ice so thick you can tank five castings of disintegrate but if a Kobold comes up and whacks your icy tomb with a stick, you better make a DC 10 concentration check.

Actually ToL causes Incapacitated, which ends Concentration anyway, so no checks needed.

Other than that though, I agree with you that a case by case basis approach can work.

[EggKookoo]

No. I’m not sure why you think I need to see tHPs how you think I should, or why you’ve decided multiple times to try and explain my view, but you’re doing a poor job of it.

Probably because I've made no attempt to explain your point of view. I don't know where you're seeing that. The closest I've come is to basically say that within your point of view (damaged != undamaged) you can still view temp hp as inherent to the creature. Or at least I think you can. Maybe I'm wrong but it makes sense to me.


You don’t have to view HPs as “discrete things” that exist in-game, to see an issue with explaining how something can be damaged and undamaged at the same time. Either something has taken damage, or it hasn’t.

At the same time, it makes no sense that a feature that provides damage resistance (or vulnerability) should apply when you're not taking damage. Therefore, temp hp should be deducted first, then damage resistance/vulnerability should be applied to any leftover actual hit points. But at least per Crawford the reverse is true. Same with the 3pt deduction from Heavy Armor Master. Those three points are deducted first, then the remaining is applied to your temp hp. How does any of that work if losing temp hp isn't "taking damage?" It's even weirder in this case because HAM's deduction is based on damage type.


Either a knife attack damages a character, or it doesn’t. If it damages a character, then that character cannot also be undamaged (again, unless something else fixes the damaged in its entirety). If in your game you want to describe a damaging attack as one that almost hits, but doesn’t, cool. But that’s still then damage done to a character, and it makes no sense to then also describe that character as “undamaged.” I also find that to be a difficult way to differentiate between “healable damage” and “non-healable damage” in that some misses will just be misses, some misses will be missed that do damage and require healing and some misses will do damage and not require healing. I also find issues with why anyone would waste magic to “heal” someone who isn’t actually hurt (but has just lost their “luck points”), but we’re getting off topic.

However you want to describe taking damage, then that means there’s an inconsistent when describing something that takes damage as being undamaged.

So Crawford's words are: "When temporary hit points absorb damage for you, you're still taking damage, just not to your real hit points." (https://twitter.com/JeremyECrawford/status/503958007177166848)

There's an interesting tidbit in here. He's saying you have (at least) two elements or properties that are capable of being damaged: Your actual hit points and your temporary hit points. When you are attacked, your temp hp take the brunt and become damaged. Your actual hit points remain full. Your hit points are undamaged while your temp hp are damaged.

You are, then, both damaged and undamaged.

Metaphorically, maybe, think of it as you grow a temporary layer of thicker skin, and it's that new skin that gets lacerated. Or something similar. I mean, if you like to imagine it in-fiction as a physical effect.

[Contrast]

I think the buff is the main issue. I disagree on counting tHP as taking damage as making sense in-game: if your tHP are “a protective magical force...manifesting as a spectral frost that covers you and your gear,” why then are you “taking damage” when a dagger only scrapes the frost, neither penetrating the protective magic force nor even touching the character’s body? Nothing actually caused HP loss to the character (that is, damaged them), so why then, are they considered to have taken damage?

Ultimately, though, I agree tHP cause issues if played as anything other than “additional, non-recoverable HPs”, and as such would suggest its easier to play them that way. I just disagree that viewing tHP that way in-game makes sense.

I feel like the difference probably lies in that we appear to have a difference of opinion on if damage can be described as happening to a PC while under the effect of THP. I would be totally ok with describing damage happening to them, just of a sufficiently mitigated nature that they are able to shrug it off/carry on as normal/they've healed up by the time the THP wear off.

If someone was under the effects of Heroism for 5THP a round and being attacked by a commoner with a dagger for 1d4 damage, I would probably not describe how the dagger glanced harmlessly off their skin but rather how none of the blows seemed to be striking true and those that did seemed like papercuts, not even bleeding. In the case of AoA I don't think I would describe things any differently than I normal would for any armour wearing PC taking damage.

Consider a character in an action movie who wraps a bandage around their broken ribs and takes some pain killers. They're still very much injured but suddenly can take a load more damage again - that's how I imagine THP.

[Aimeryan]

First off, I agree the implications of playing tHP as RAW states (“a buffer”) has significant changes, and I’m not saying that’s how they should be played. AoA becomes a much more effective spell, for instance. And yes, you can get into some interesting questions of whether additional effects would activate to further increase the effectiveness of using tHP (though the official rules already allow this with Abjurer’s Ward so it’s not necessarily game breaking or something outside what the game officially allows)

However, the RAW states “Whenever a creature takes damage, that damage is subtracted from its hit points” and “Temporary hit points aren’t actual hit points; they are a buffer against damage, a pool of hit points that protect you from injury.” RAW, tHP prevent the character from actually taking damage.

This should probably be errata’d as i imagine it’s one of the cases where the writers used a word (in this case “damage”) both as its common English meaning and as it’s game specific meaning (that is, damage=HP loss) without differentiating between the two.

[...]

I think the buff is the main issue. I disagree on counting tHP as taking damage as making sense in-game: if your tHP are “a protective magical force...manifesting as a spectral frost that covers you and your gear,” why then are you “taking damage” when a dagger only scrapes the frost, neither penetrating the protective magic force nor even touching the character’s body? Nothing actually caused HP loss to the character (that is, damaged them), so why then, are they considered to have taken damage?

Ultimately, though, I agree tHP cause issues if played as anything other than “additional, non-recoverable HPs”, and as such would suggest its easier to play them that way. I just disagree that viewing tHP that way in-game makes sense.

I suspect this may have came from different writers contributing to the same mechanic. It is possible some writers (AoA, ToL, etc.) meant to have the tHP be a buffer against damage, while other writers (Heroism, etc.) meant to have the tHP be just an increase in effective hit points. Interestingly, some spells that grant more effective health do so by increasing maximum HP, instead; Aid and Heroes' Feast come to mind.

~~~


At the same time, it makes no sense that a feature that provides damage resistance (or vulnerability) should apply when you're not taking damage. Therefore, temp hp should be deducted first, then damage resistance/vulnerability should be applied to any leftover actual hit points. But at least per Crawford the reverse is true. Same with the 3pt deduction from Heavy Armor Master. Those three points are deducted first, then the remaining is applied to your temp hp. How does any of that work if losing temp hp isn't "taking damage?" It's even weirder in this case because HAM's deduction is based on damage type.

Some resistance sources it would make sense for; Blade Ward, for example, provides resistance via 'trace a sigil of warding in the air' - why would this not come into effect before the magical frost covering you from AoA?

[EggKookoo]

Some resistance sources it would make sense for; Blade Ward, for example, provides resistance via 'trace a sigil of warding in the air' - why would this not come into effect before the magical frost covering you from AoA?

Sure, but the RAI (if not RAW) supports that so all is well.

Note that the description of blade ward doesn't say the sigil itself is what's protecting you (like it's some kind of floating barrier). The descriptive text is ambiguous about it but the implication from the mechanics is that the sigil is just the activation of the power, and the damage resistance is applied to your body. There's nothing about insuring that an incoming attack must pass through the sigil, or that another creature near you can benefit from it as if it was an actual object in the air, or anything that supports that visualization. You just gain resistance upon casting it, which (via the rules as we understand them) bubble up to any temp hp you may happen to have.

Is there a mechanic anywhere that explicitly provides resistance as a kind of force field effect?

[Aimeryan]

Is there a mechanic anywhere that explicitly provides resistance as a kind of force field effect?

'Explicit' is difficult. 'Paraphrase', yes, a few:

Absorb Elements - Spell absorbs some of the energy before it affects you.
Fire Shield - A shield of flames.
Shadow of Moil - Flame-like shadows that resist radiant damage.


There are also the numerous 'Investiture of ...' spells; the damage has to pass through it before getting to you, which lessens it (resistance). The problem here is that because they are so close to the skin it is likely any temporary HP force fields would have been passed through, already. So, a force field effect but not one that is probably applicable here.

[Sparky McDibben]

I think this has been a really good conversation. Thanks for everyone's opinion. I think I'm going to rule that damage to temp hp doesn't cause a concentration check. That's just in my game, of course, but y'all do you!

[EggKookoo]

'Explicit' is difficult. 'Paraphrase', yes, a few:

Absorb Elements - Spell absorbs some of the energy before it affects you.
Fire Shield - A shield of flames.
Shadow of Moil - Flame-like shadows that resist radiant damage.


There are also the numerous 'Investiture of ...' spells; the damage has to pass through it before getting to you, which lessens it (resistance). The problem here is that because they are so close to the skin it is likely any temporary HP force fields would have been passed through, already. So, a force field effect but not one that is probably applicable here.

Thank you for doing my homework for me. :smallsmile:

I guess what I mean by a force field effect is one where there's a definite barrier of some kind that exists in a particular (if changeable) location in space that imparts resistance to some or all of the damage passing through it. Most such effects (shield or the varies wall of... spells) either provide a bonus to AC or outright block damage completely. This jives with how D&D handles shielding- and armor-like systems in that they're deflection/AC-based rather than resistance/HP-based.

[Aimeryan]

Thank you for doing my homework for me. :smallsmile:

I guess what I mean by a force field effect is one where there's a definite barrier of some kind that exists in a particular (if changeable) location in space that imparts resistance to some or all of the damage passing through it. Most such effects (shield or the varies wall of... spells) either provide a bonus to AC or outright block damage completely. This jives with how D&D handles shielding- and armor-like systems in that they're deflection/AC-based rather than resistance/HP-based.

The 'Wall of ...' spells do that in one way or another. Wall of Water, in particular, halves any fire damage passing through it.

[EggKookoo]

The 'Wall of ...' spells do that in one way or another. Wall of Water, in particular, halves any fire damage passing through it.

Oh, in Xanathar's...

That's an interesting one. It doesn't provide resistance per se, just cuts the damage in half. I imagine if that damage struck a fire-resistant creature it would be halved again?

We're getting off topic now and the OP's original question has been answered. I guess if there's interest we could ignite a new thread?