D&D 5E The mathematics of D&D–Damage and HP

[tetrasodium]

There are several other things to consider with attacks:

1. It is much easier to gain advantage on an attack roll than impose disadvantage on a saving throw.
2. There's no such thing as Legendary AC you have to burn through to score a hit.
3. Magic weapons are far more common than spell-boosting items.
4. There's no such thing as critical save damage
5. Multiple attacks benefit more from bonuses (whether magic items or spells like Enlarge)
6. Once you have a magic weapon, you never really need to worry about damage resistance again

So, on paper, it might not initially look like martials are that big a deal, but at the table (at least, didn't at a first reading of the 5e rules when I first got them), they really do dump out a lot of damage.

All good points & I'm glad that the thread didn't die after you posted that (very bad) chart back in 75 like it looked. You can't model damage over time with different hit rates using one line. The chart would need one line for each % chance to hit unless you are modeling something misleading or hard to visualize like damage over a specific number of rounds. I think it was probably a well meaning mistake rather than an attempt at obfuscation through "lies damn lies and statistics" though so moving on

The data below assumes +5 to relevant stat for both caster & martial. The specific damage type is irrelevant as it's easier to just model one with resistance & one without just as +1 +2 +1d6 weapons are easier to give their own lines. I'm going to give the martial the best odds to prove 5e still plunges into LFQW rather than inverting it though & say that the caster is using a d12 cantrip like toll the dead & the martial a d10 weapon like a longsword rather than modeling every possible choice.

I'm not going to make a pretty graph but I'll save others time & attach the sheet below
at 100% hit rate, right away you can see that the numbers aren't even close to supporting LFQW & at least with 100% hit rate/0% save chance it's massively inverted

Spoiler: math numbers

..

Those numbers are massively skewed to an eye popping degree because every attack the longsword deals +5 from the relevant attrib and an extra +1 +2 or +3 while the cantrip never adds +5 from the relevant attrib and never adds the +1 +2 or +3 more than once per round

This next set is the same numbers with a 75% hit chance & 25% save chance. Since this is played out over rounds I don't need to model it by fiddling with average damage & can just show an accumulation of the numbers that actually deal damage. every third attack will miss & every fourth cantrip will save for none. Frankly the numbers at 100% are so bad that I questioned if there was even a point but decided to do it anyways for the sake of people who are struggling with the math (which is fine if someone is having trouble keeping up).

Spoiler: math numbers @75%/25% 2 attacks & 2d12

The first round of longsword data assumes there was a miss then every fourth attack or cast is a miss or save. That first round inverted for the cantrip with the first round assuming no save just because it was easier to model that way. Since this is showing damage over time in rounds it doesn't really matter.
The numbers are so stark that I'm not going to model what happens with only one attack with 75% hitrate & will jump straight to

Spoiler: 2 attacks/2d12 with a 50%

at 50% the numbers are still horriffic & show just how much leveled spells need to bring to the table. If leveled spells were available in dramatically higher amounts that would be easy, but the numbers are so grossly out of wack that they need to be things like "every fireball hits the max number of targets and they mostly fail their saves" to bridge the gap because you can't cast a cantrip+a spell like you can attack+sneakattack or attack+action surge & already leveled spells barely just kinda break even rather than pull ahead

I tried to stack the deck in favor of showing LFQW was still a thing as much as possible & my reasoning was because for whatever reason Wotc chose to have both higher damage and more attacks on the weapon side of weapon to cantrip damage so the damage won't ever invert even if you get to very low hit rates. Paradoxically Wotc took that inverted LFQW one step further with the bewildering damage resistance magic resistance ac's almost guaranteed to hit excessive concentration use often unused by design spells & legendary resistance situation. If DR were still a thing on more than a handful of almost never used plant creatures or vulnerability to energy types were quite common there could conceivably be situations where the cantrip user would pull ahead but that's not the case either

edit:I originally flubbed the sheet by including strength looking at it & saying "oh I left out strength" to add it again

 

[fearsomepirate]

All good points & I'm glad that the thread didn't die after you posted that (very bad) chart back in 75 like it looked. You can't model damage over time with different hit rates using one line. The chart would need one line for each % chance to hit unless you are modeling something misleading or hard to visualize like damage over a specific number of rounds. I think it was probably a well meaning mistake rather than an attempt at obfuscation through "lies damn lies and statistics" though so moving on

The chart was the Y% chance of doing at least X damage in a single round. I find this much more conceptually useful than DPR. Unfortunately, Anydice does not allow me to label axes. Probably should have been explicit about what they were.

So, for example, this chart shows that an 13th-level duelist fighter has a ~75% chance of doing at least 23 damage with his +2 longsword (target AC is 19 btw), while a wizard with Fire Bolt has a much lower chance , around 10%, of hitting that hard.

The reason I prefer this expression is that in a given fight, what is most important is whether you kill the enemy.

 

[tetrasodium]

The chart was the Y% chance of doing at least X damage in a single round. I find this much more conceptually useful than DPR. Unfortunately, Anydice does not allow me to label axes. Probably should have been explicit about what they were.

So, for example, this chart shows that an 13th-level duelist fighter has a ~75% chance of doing at least 23 damage with his +2 longsword (target AC is 19 btw), while a wizard with Fire Bolt has a much lower chance , around 10%, of hitting that hard.

View attachment 134442

The reason I prefer this expression is that in a given fight, what is most important is whether you kill the enemy.

That explains why I was confused by your chart. I agree that damage per round is not an especially useful metric by itself as there are too many other variables to consider & that's why I did numbers for damage accumulated across rounds or what in WoW terms would be the total dataset of damage output over the course of a raid that gets used to calculate DPS, average damage, & so on.

WoW raids are a great example of why casters miss the mark so badly in 5e as it's organized by what everyone brings to the table then filling extra slots with quality of life stuff. in 5e we have the sword & board high hp high ac tank wearing both the crown for tank as well as having a damage output capable of laughing at a lower hp cloth wearing caster. That sort of situation is so flaming pants on head backwards & wrong that it runs straight into either "yea xyz creature is mostly immune to spells because X" or "we found a bug in the code & a htfix is rolling out shortly" type territory.

Extending the WoW metaphor it's fine for a class to have terrible damage output and terrible durability if it brings serious utility to the table such as battlefield control, buff/debuff, healing, or damage mitigation... but the way rests, the inability to drop below zero hp, & death by massive damage being pegged to max rather than current HP largely mitigates the last two there while spell slots & concentration along with monster ACs that are almost guaranteed to let a PC hit largely gets rid of the rest. Sure a well timed web can really save the day, but it can't be well timed if the baddies aren't all within a 20ft cube (smaller area than past editions when LFQW was still a thing) & the monsters get a save every round now and if they fail their save they just need to take 2d4 damage from one of the most common energy types or use their action to make a strength check.

One could say things like "but teleport" or some other noncombat utility spell & there might be a case to be made, but it's certainly not one supported by WotC's hardcovers when things like the wandering emporium don't even have a circle to learn.

 

[fearsomepirate]

The thing is that in 5e, combats are so few rounds that the law of large numbers doesn't apply to them. Sure, over the campaign, you'll do total damage in keeping with your DPR. But in a single encounter? You've got 3 to 5 turns, tops. So if the Wizard casts Banishment and fails, or a Rogue misses his attacks in the first and second rounds, everything can go sideways fast.

I am mostly pretty happy with casters 5e, as LFQW is dead, and martials now own the single-target damage niche. However, it can be hard for players to really grasp this, as damage dice simply have the lowest cognitive load. When faced with choosing between throwing a wad of damage dice on the table or various status effects, most players will simply choose damage, whether it's Magic Missile over Protection From Evil at low level, or Disintegrate over Otto's Irresistible Dance at high level.

 

[tetrasodium]

The thing is that in 5e, combats are so few rounds that the law of large numbers doesn't apply to them. Sure, over the campaign, you'll do total damage in keeping with your DPR. But in a single encounter? You've got 3 to 5 turns, tops. So if the Wizard casts Banishment and fails, or a Rogue misses his attacks in the first and second rounds, everything can go sideways fast.

I am mostly pretty happy with casters 5e, as LFQW is dead, and martials now own the single-target damage niche. However, it can be hard for players to really grasp this, as damage dice simply have the lowest cognitive load. When faced with choosing between throwing a wad of damage dice on the table or various status effects, most players will simply choose damage, whether it's Magic Missile over Protection From Evil at low level, or Disintegrate over Otto's Irresistible Dance at high level.

Banish is on the spell list for cleric paladin warlock wizard and bonus spell lists for three paladin oaths so it's not like that's the wizard's saving grace or that other cantrip casters not named warlock don't have it just as bad as the wizard. That "if the wizard fails" is all the more reason having so many thumbs on the scale to make sure they never shine too bright even when it's something they should shine at is all the more problematic. Keep in mind that neither of our numbers included things like GWM & the hit rates for attacks targeting monster AC is so high that -5 to hit is still almost certain to hit in most cases. "If the wizard fails" they typically fail hard & they spend a spell slot to even try but if the caster does it's rarely all that impressive enough to bridge the gap in ways anyone cares about even if they succeed. Banishment is a symptom of the problem not a side road that avoids it

 

[pemerton]

@tetrasodium, in your charts where is the extra +5 damage coming from? Ie a longsword does 1d10 (weapon base) + 5 (stat) +n (magic) +5 (from what? critical? but why would the fighter be critting 100% of the time?)

I also had trouble following some of your formulas - eg in the 4 round column for 75% hit chance with two attacks, why does the damage step up by 32 (ie two round's worth) compared to the 3 round column? If this is Action Surge, why isn't it modelled in the 100% 1 attack column? From then on it seems that your columns step up in a +16, +32 pattern but why?

It seems to me that a fighter with +5 stat and +1 longsword with 95% chance to hit (best possible) does an average of 5.5 (base) +5 (stat) +1 (magic) + 5.5/19 (crit, which happens on a 20 ie 1 in 19 rolls) on a hit, = average of 11.8 (rounding up very slightly) on a hit = average of 11.2 per attack. What have I missed? - improved crit range will lift it a tiny bit; manoeuvre dice will lift it a noticeable bit; but I'm not seeing how you're lifting it to 16 per attack.

When you say your numbers show "how much leveled spells need to bring to the table" I think they ought to: if a wizard does the same damage as a fighter, or close to it, before those spells are brought to the table then the wizard will be obviously broken in their power, dominating in and out of combat!

 

[fearsomepirate]

Banish is on the spell list for cleric paladin warlock wizard and bonus spell lists for three paladin oaths so it's not like that's the wizard's saving grace or that other cantrip casters not named warlock don't have it just as bad as the wizard. That "if the wizard fails" is all the more reason having so many thumbs on the scale to make sure they never shine too bright even when it's something they should shine at is all the more problematic. Keep in mind that neither of our numbers included things like GWM & the hit rates for attacks targeting monster AC is so high that -5 to hit is still almost certain to hit in most cases. "If the wizard fails" they typically fail hard & they spend a spell slot to even try but if the caster does it's rarely all that impressive enough to bridge the gap in ways anyone cares about even if they succeed. Banishment is a symptom of the problem not a side road that avoids it

I didn't bring up Banishment as the be-all end-all of Wizard spells. I simply mentioned it as an example of why average-based analysis isn't all that helpful.

For the record, I haven't seen wizards struggle to shine in 5e. Outside of AoE, they do best when they think about how best to help the party rather than how best to roll a lot of damage dice.

 

[tetrasodium]

@tetrasodium, in your charts where is the extra +5 damage coming from? Ie a longsword does 1d10 (weapon base) + 5 (stat) +n (magic) +5 (from what? critical? but why would the fighter be critting 100% of the time?)

Human error, I'll update the images in a minute

I also had trouble following some of your formulas - eg in the 4 round column for 75% hit chance with two attacks, why does the damage step up by 32 (ie two round's worth) compared to the 3 round column? If this is Action Surge, why isn't it modelled in the 100% 1 attack column? From then on it seems that your columns step up in a +16, +32 pattern but why?

Every third attack misses so there is one successful attack, two successful attacks one successful attack etc

It seems to me that a fighter with +5 stat and +1 longsword with 95% chance to hit (best possible) does an average of 5.5 (base) +5 (stat) +1 (magic) + 5.5/19 (crit, which happens on a 20 ie 1 in 19 rolls) on a hit, = average of 11.8 (rounding up very slightly) on a hit = average of 11.2 per attack. What have I missed? - improved crit range will lift it a tiny bit; manoeuvre dice will lift it a noticeable bit; but I'm not seeing how you're lifting it to 16 per attack.

I didn't include anything for crits because it complicates the math & would only skew even further

When you say your numbers show "how much leveled spells need to bring to the table" I think they ought to: if a wizard does the same damage as a fighter, or close to it, before those spells are brought to the table then the wizard will be obviously broken in their power, dominating in and out of combat!

 

[tetrasodium]

I didn't bring up Banishment as the be-all end-all of Wizard spells. I simply mentioned it as an example of why average-based analysis isn't all that helpful.

For the record, I haven't seen wizards struggle to shine in 5e. Outside of AoE, they do best when they think about how best to help the party rather than how best to roll a lot of damage dice.

It's one of the better ways a wizard can do nondamage stuff, but casters have a huge damage gap significant hp gap & generally a notable AC gap so the nondamage stuff needs to bridge the gap & then some to make up for the times they are conserving spell slots or don't have the situationally perfect spell prepped.

Frankly there are too many thumbs on the scale for that to happen as combined they add up to an overwhelming combo

• Magic weapon of any kind ignores resist to nonmagical bps while energy resist is hugely overused but never goes away. This is bad enough that you almost immediately after Tasha's saw folks post order of scribes spell guides that list all the b/p/s spells & spells that go from rarely useful to great when they do things like switch from poison to bludgeoning damage.
• Concentration is overused on spells so for example web banish magic weapon & enlarge are all some level of ok to good spells but only one can be used as all of them are concentration
• Magic resist to give advantage against saves is overused while monsters with difficult to hit ACs are less than common.
• Feats exist to specialize for weapon damage (ie GWM & such) or defense (ie medium/heavy armor master) while very little specialization & synergy can be obtained through feats for casters with web+telekinetic get back in there one of the very few exceptions
• A huge number of spells generally fall under the "almost good" or "unused by design" labels, often due to excessive saves, secondary ways out, or range/aoe coverage that got shrunk to something that really kinda requires the GM to set the stage by putting all the baddies close together. Web is a good example of an ok to good spell that could have been great. Compare 3.5 & 5e web
  
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  • 10min per level to 1hr. This part is a wash since caster level 6 is nothing & will exceed it from 7th on but it's almost never going to be needed
  • Reflex negates to dex negates is the same
  • No saves each round to strength save each round
  • DC20 strength check or DC25 escape artist check to dc=caster's spell save DC each round is a huge nerf that more than consumes the hit from move 5 feet for every 5 points you beat dc10 by since realistically caster dc is never going to be 20-25 in 5e.
  • 20foot radius to a 20foot cube?... that's about half the aoe coverage
  • 100ft+10ft/caster level to 60 ft?... That's a gigantic drop in range & especially notable given the insane range bump on ranged weapons.
  • spell resistance:no to magic resist grants advantage on the save.... There don't even exist spells to bypass magic resistance in 5e, this is a gigantic nerf.
  • fire & forget to concentration so your web might drop if you get his & even if that's not an issue you now can't cast web with most other buff/debuff/DoT/Area Denial spells like haste curse magic weapon elemental weapon enlarge wall of whatever(fire/ice/etc) & many more despite many of those spells themselves also getting a similar set of petty nerfs
• That concentration cherry on top of all the other petty nerfs & hinderances adds up to ensure the caster never uses them in conjunction to go from doing something to occasionally really stepping out from being the squishy character with mediocre damage into the spotlight as more than "well I guess that was a useful speedbump" or "I guess that helped a little"

 

[pemerton]

I don't have 5e play experience. I do have a lot of 4e play experience. In 4e, AoE action denial is very strong. The fact that it has a duration of only a round or two doesn't undermine its strength. I'm not aware of any reason to make me think that it would be markedly less strong in 5e.

 

[fearsomepirate]

It's one of the better ways a wizard can do nondamage stuff, but casters have a huge damage gap significant hp gap & generally a notable AC gap so the nondamage stuff needs to bridge the gap & then some to make up for the times they are conserving spell slots or don't have the situationally perfect spell prepped.

I think it largely does. Most of the concentration spells do things like grant ongoing advantage, deny enemies their action, set up auto-crits, and that sort of thing. I don't think Web is underpowered just because the 3.5 spell is more powerful. It's a perfectly good 5e spell that combines action denial and strong debuffs.

• Concentration is overused on spells so for example web banish magic weapon & enlarge are all some level of ok to good spells but only one can be used as all of them are concentration

I agree with this, but it's not an issue until high levels. I am considering taking this out for a spin as a house rule:

"If you are concentrating on a spell, you can concentrate on one other spell that is either at least twice the level of your current spell or no more than half its level. If you take damage, the same concentration check applies to both spells."

• A huge number of spells generally fall under the "almost good" or "unused by design" labels,

Let's be fair, most spells in every non-4e edition have been crap.

• spell resistance:no to magic resist grants advantage on the save.... There don't even exist spells to bypass magic resistance in 5e, this is a gigantic nerf.

Spell resistance in 5e isn't the same as 3.5; so this is not an apples-to apples comparison. There are plenty of things a wizard can do if a monster has good saves. Cast a buff spell. Cast a spell that uses your spell attack instead of imposing a save. Summon minions. Use one of the no-save spells like Heat Metal, Cloud of Daggers, or Wall of Fire.

I don't have 5e play experience. I do have a lot of 4e play experience. In 4e, AoE action denial is very strong. The fact that it has a duration of only a round or two doesn't undermine its strength. I'm not aware of any reason to make me think that it would be markedly less strong in 5e.

Action denial is extremely powerful in 5e. At the rate players tend to do damage, a round of not doing anything is around a quarter of the entire combat.

 

[FrogReaver]

So, I see very often DPR, Damage Comparisons, and Health being discussed at-length playing D&D.

Often times, in White-Room theory-crafting scenarios, someone will talk about the damage a character can inflict on a target and compare that damage to the health of said target.

For example, someone could talk about how a single scorching ray kills a goblin because 2d6 = 7 average damage and a goblin's average HP is 7. Therefore, if the ray hits, its essentially a guaranteed kill, right?

But we're forgetting the fact that when average damage = 7, it actually means there's only a 58.33% chance to actually kill that enemy. This is because while 7 is the most likely sum of combinations, it still only accounts for 16.66% of the total possible combinations.

So if you have a 65% chance to-hit a goblin with 2d6 damage, you actually only have a 38% chance of killing the goblin, which is really low if you're taking a whole action. Its possible, but its very low.

Now, reverse that but for HP. Imagine the DM decided he wanted to roll for health but he waited until after the grimlock first takes damage. The damage is rolled and it ends up 11, the DM decides to roll the grimlock's health which is 2d8+2. The damage should kill, right? Well, its actually around 50% as well.

If you combine those two mathematical models, the actual percent chance of certain attacks killing a character with rolled dice becomes much swingier. Of course, most DM's don't roll health for their monsters, but it does lead to interesting probabilities.

I just wanted to discuss exactly how damage can be a misleading factor when talking about damage and its relation to HP.


TL;DR
When average damage = average health, it isn't a guaranteed kill. Its actually roughly a 50% chance to kill. Be considerate of these facts when discussing DPR.

Do we have examples of this mistake being regularly made? It's egregious if it is, but I don't know that I've really seen it, so just wanting to make sure we aren't about to beat up on something fictional.

Talking more on the theory side - as hp goes up and damage becomes spread over more attacks then this phenomenon you are talking about becomes much less pronounced. Essentially the probability distribution of damage dealt starts to more and more resemble a bell curve. Meaning this effect you speak of is only particularly present for low hp enemies.

 

[FrogReaver]

In D&D, I do not care primarily about the amount of damage I do. I care about killing the monster before it hurts the party more. If our Marilith is down to 70 hit points, the chance that Finger of Death will kill her is less than 1%, and the chance that Disintegrate will kill her is 30%. So, despite FoD doing more average damage, it is not necessarily the "theoretically correct choice" to use it. If the Marilith goes next, it's arguably smarter to use the spell with the most potential to end the threat.

This isn't exactly true. The higher average damage spell will typically end the encounter on average in fewer rounds. Consider, when disintigrate misses how many rounds then? There are times when the higher variance attack is better - for example you are facing a nearly certain PC death if the enemy gets one more turn. But if that's not the case then the safest course of action is to take the higher chance of killing the enemy on average faster, which Finger of Death accomplishes due to it's higher DPR.

Then there's also the fog of war and timeliness to consider, where you likely don't know the Marilith's current hp value to any degree of certainty - which rather complicates using actual probabilities as a guide. Then calculating such probabilities on the fly in a timely manner even if you have all the values is the next complication. So when all is said and done higher DPR won't always be the "best" answer, but quite a bit more often than not it is going to be - which makes it a great heuristic that is relatively easy to calculate.

 

[tetrasodium]

I think it largely does. Most of the concentration spells do things like grant ongoing advantage, deny enemies their action, set up auto-crits, and that sort of thing. I don't think Web is underpowered just because the 3.5 spell is more powerful. It's a perfectly good 5e spell that combines action denial and strong debuffs.



I agree with this, but it's not an issue until high levels. I am considering taking this out for a spin as a house rule:

"If you are concentrating on a spell, you can concentrate on one other spell that is either at least twice the level of your current spell or no more than half its level. If you take damage, the same concentration check applies to both spells."



Let's be fair, most spells in every non-4e edition have been crap.



Spell resistance in 5e isn't the same as 3.5; so this is not an apples-to apples comparison. There are plenty of things a wizard can do if a monster has good saves. Cast a buff spell. Cast a spell that uses your spell attack instead of imposing a save. Summon minions. Use one of the no-save spells like Heat Metal, Cloud of Daggers, or Wall of Fire.



Action denial is extremely powerful in 5e. At the rate players tend to do damage, a round of not doing anything is around a quarter of the entire combat.

The problem with overuse of concentration on almost good spells is that it prevents the caster from using them together to keep the naughty word from hitting the fan while everyone is watching he trainwreck they all know is coming. Take the marilith example @FrogReaver brought up, if you've ever read their statblock or fought them you remember that as one of the few monsters built like a PC they are a serious threat to anyone they choose to squash thanks to a +9 to hit 40ft speed and seven attacks on top of teleport, parry (eats a reaction kickass!!!), magic weapons (probably pointless to PCs), magic resistance (advantage on all saves...), resistance to cold fire lightning & nonmagical BPS. on a cr 16 creature with 18 ac the fighter/rogue/ranger/paladin etc does not need to roll all that high & that reaction parry only kicks in once per round while a caster needs to beat str+9 con+10 wis+8 cha+10 dex+5 saves made with advantage for an effective str+14/con+15/wis+13/ dex+10. Even if the caster bypasses the save it takes half damage from cold/fire/lightning & full damage from the fighter/rogue/etc's +1 weapon. This would be reasonable if it was a highly unusual situation rather than dirt common monster design or if there were a lot of monsters that flipped the tables & put the martials behind the 8ball like the old wraith/ghoul/trog/etc & creatures with dr25 10 15/x did but all of those creatures were generally removed or neutered to no longer be much worry That marilinth should be the time that a wizard calls upon every spotlight & steps up onto a podium as they buff/debuff/control the situation into something not so scary but concentration ensures even if prepared they can't do more than one.

Lots of people talk about allowing multiple concentrations to be going, but there's a reason few ever talk about doing it & that's because the same concentration is used for spells that never should have been concentration as well as spells where concentration is likely to be an actual important limiter & sorting out which is which and tweaking spells that need tweaking is a lot of work thanks to the brainless application of concentration on so many spells and cantrips.

Spell resistance is different fromn3.5 yes, it's actually more powerful in a lot of ways due to beating SR in 3.5 generally not being a huge hurdle unless the SR itself was the creature's strength. The fact that it's different is reason to use it even more sparingly than before You talk about how a wizard can simply cast a buff spell if a monster has good saves, sure if it's prepared, and it's even a useful buff, and that useful buff is at all useful to the situation at hand.... You may play & wotc may test with every encounter faced by PCs built from the ground up for an optimized steamroll through a given encounter knowing the encounter they are building for; that however is very much not the norm & has little place in discussions like this.

Those (de)buff spells need to have a wide enough scope of useful situations to justify taking a prep slot over something that does like web fireball & so on. Exactly what buff spells are you casually throwing out as expected to be prepared?

• enlarge? +1d4 damage for one ally & take up more squares so more things can attack at once in addition to the marlinth?.... Oh yea it's concentration too
• enhance ability? rofl.
• Dragon's breath so instead of taking a full set of attacks with +attrib bonus & +weapon mods on each attack it can take 3d6 save with advantage to a damage type selection loaded with types it resists?
• Flame arrows? a concentration 1hr duration spell that adds +1d6 fire to twelve pieces of ammunition? Because it's so good that even with a 1hr duration & concentration requirement it still needed to be limited to twelve pieces of ammunition...
• gasseous form?.. this is unlikely to help at all
• greater invis on the rogue? Usefulish if advantage isn't obtained through other always on no cost means like pack tactics or flanking.. oh yea it's concentration too & has a 1 minute duration,
• Haste? One of the better buffs yes, but it too is 1min duration & concentration.
• so on & so forth....

Don't jut say cast a (de)buff instead of web & save for half spells, be explicit & specifically name the go to (de)buffs either lacking concentration or that you think are so good that they justify all the lead thumbs on the scale.

 

[fearsomepirate]

Mariliths have Truesight, so Greater Invisibility won't do much for you.

Don't jut say cast a (de)buff instead of web & save for half spells, be explicit & specifically name the go to (de)buffs either lacking concentration or that you think are so good that they justify all the lead thumbs on the scale.

Some good choices for fighting high-level fiends (resist fire/ice/zap/mundane, Magical Resistance):

1. Protection From Evil. Despite being a lowly first-level spell, it's really good against demons. Cast it on a warrior.
2. Enlarge/Reduce. Cast this on somebody with proficiency in Athletics so they can Shove the Marilith prone and Grapple it on their next turn.
3. Haste. Cast this on anyone with a -5/+10 feat, a paladin, or barbarian. Don't waste it on a Rogue or typical Fighter.
4. Bigby's Hand, upcast. The scaling on this almost seems like an oversight.
5. Ray of Enfeeblement. Initially activates on a successful attack, not a failed save. Sure, the Marilith is highly likely to save out of it after her next turn, but you're at least 14th level, you can cast this all day if you want.
6. Wall of Light. Good if you can put this down in such a way that the Marilith can't attack the party without standing in it.
7. Polymorph to T-Rex. While the Marilith resists its damage, its bite automatically grapples & restrains on a hit.
8. Otto's Irresistible Dance. This takes an action to save out of.
9. Tenser's Transformation. If you get any time to prep, can be pretty dope.
10. Mordenkainen's Sword. I'm kidding, this spell is crap. Just wanted to see if you were paying attention!

 

[tetrasodium]

Mariliths have Truesight, so Greater Invisibility won't do much for you.


Some good choices for fighting high-level fiends (resist fire/ice/zap/mundane, Magical Resistance):

1. Protection From Evil. Despite being a lowly first-level spell, it's really good against demons. Cast it on a warrior.
2. Enlarge/Reduce. Cast this on somebody with proficiency in Athletics so they can Shove the Marilith prone and Grapple it on their next turn.
3. Haste. Cast this on anyone with a -5/+10 feat, a paladin, or barbarian. Don't waste it on a Rogue or typical Fighter.
4. Bigby's Hand, upcast. The scaling on this almost seems like an oversight.
5. Ray of Enfeeblement. Initially activates on a successful attack, not a failed save. Sure, the Marilith is highly likely to save out of it after her next turn, but you're at least 14th level, you can cast this all day if you want.
6. Wall of Light. Good if you can put this down in such a way that the Marilith can't attack the party without standing in it.
7. Polymorph to T-Rex. While the Marilith resists its damage, its bite automatically grapples & restrains on a hit.
8. Otto's Irresistible Dance. This takes an action to save out of.
9. Tenser's Transformation. If you get any time to prep, can be pretty dope.
10. Mordenkainen's Sword. I'm kidding, this spell is crap. Just wanted to see if you were paying attention!

PfE is a 10 minute buff that does provide a good benefit to one person... if they are targeted... and it requires concentration so you won't be using any other concentration spells
Enlarge to grapple the marlinth? are you not familiar with the

Spoiler: grappled condition

Prone is not the pananancia you are making it to be either

Spoiler: prone

You've used an action to buff an ally with a 1 minute concentration spell so they can burn two attacks in order to impose disadvantage on the warlock & any other ranged attackers? This is slightly better than casting the darkness spell that blinds everyone but devils sight warlocks & anything with truesight. It's certainly going to get the group's attention sure, but probably not in a good way.

Haste is indeed a good spell, it's also a 3rd level single target concentration spell with a 1 minute duration so you won't be using any other concentration spells & it will probably end before the next fight so it needs to reallly step up & absolutely trivialize things for those ten rounds to catch up & really shine. While good, it doesn't meet tat bar.

Ray of enfeeblement? You yourself bring up the excessive saves, oh yea it's concentration too so you can't use it with haste or any of the other buff spells you are praising. As a second level spell not a cantrip even the level 14 caster you note can't "cast this all day" especially when expecting to have the target save out next round if they hit on the attack roll

Wall of light? As a 5th level concentration spell that deals 4d8 radiant & inflicts blind 1min save for half no blind if something walks through & fails a con save It's not exactly bridging that gap with advantage on a +10 con save.

polymorph one ally into a trex for 1 hour? at level 14 the fighter has 3 attacks, +5 str, at least a +1 weapon& prof bonus of +5 for +11 to hit vrs the trex +7 4d12/3d8 two attacks... You should probably read the statblock for trex closer

Spoiler: here it is do you spot the problem?

This is another "buff" that actually made things worse. the polymorph trex sounds flashy & gets tossed out as the epitome of cool/broken regularly online but at the table in actual play there are very few levels where it might even be slightly better than not casting it. As to the free grapple, I posted what grapple actually does up there in response to your enlarge point, speed zero is hardly a big help when bpb is in the next square getting beat on.

Otto's? Every round the target gets to make a wis save to break it, the marlinth is making it with +8 & advantage, oh yea as a level 14 caster you only have one level six spell slot.... Are we talking about the same game?

Tensers transfrmation... You can't cast spells & with +9 to hit the marlinth is likely to hit a great many of the seven attacks it has each round. That 50 temp hp is going to hold up like wet tissue paper in a string breeze against 6x 2d8+4 & 1x 2d10+4... Look on the bright side though you deal an extra 2d12 force if you hit with a weapon so hopefully you maxed out strength as a caster & get to attack twice?.... proficiency with weapons & armor you were obviously carrying around in your back pocket & put on before casting the spell?

Spoiler

did you not look this spell up before suggesting it?

 

[fearsomepirate]

Enlarge to grapple the marlinth? are you not familiar with the grappled condition

Yes. A Grappled creature can't stand back up. Shove -> Grapple is a popular combo with more melee-focused parties, as it grants everyone advantage.

I'm not going to go through this point-by-point, but I did read your whole reply. I'll summarize what I see as the major oversights:

1. Depending on party composition, if you find a way to grant advantage to the whole party, the Marilith lasts less than two rounds. So, if you take something like Otto's Irresistible Dance, sure, the Marilith can burn its action to have an ~80% chance of saving out it. At that point, it may be down to double-digit HP already. If it bombed initiative, it might already be dead. So all of your talk about whether this spell is worth a full ten rounds or whatever is missing the point; the combat doesn't last that long. To high-level martials, especially with advantage, 189 HP is nothing.
   
   
2. High-level casters have plenty of slots. If you didn't get a full ten rounds out of a buff, so what? Cast it again later. Slots really aren't a big problem at high level.
   
   
3. I'm assuming intelligent players. That is, I'm assuming any real-world player is taking into account party composition after the roughly 1 year or more it takes to ever be fighting a Marilith. Yeah, obviously, if your party is one melee guy + 3 ranged guys, they're not going to use the Grapple + Prone trick. Obviously, you don't use Polymorph on your most powerful melee ally. Obviously, if you are using Tenser's Transformation, you aren't rushing into the marilith's face with 8 STR and a mundane longsword. I don't think things like that need to be said.

Also:
-Wall of Light's damage is automatic if you end your turn in it; no save.
-Tenser's Transformation works with ranged weapons

Mistake on my end:
-T-Rex restraining bite doesn't work on large creatures; a marilith is large. Don't use Polymorph to fight a marilith.

 

[tetrasodium]

Yes. A Grappled creature can't stand back up. Shove -> Grapple is a popular combo with more melee-focused parties, as it grants everyone advantage.

I'm not going to go through this point-by-point, but I did read your whole reply. I'll summarize what I see as the major oversights:

1. Depending on party composition, if you find a way to grant advantage to the whole party, the Marilith lasts less than two rounds. So, if you take something like Otto's Irresistible Dance, sure, the Marilith can burn its action to have an ~80% chance of saving out it. At that point, it may be down to double-digit HP already. If it bombed initiative, it might already be dead. So all of your talk about whether this spell is worth a full ten rounds or whatever is missing the point; the combat doesn't last that long. To high-level martials, especially with advantage, 189 HP is nothing.
   
   
2. High-level casters have plenty of slots. If you didn't get a full ten rounds out of a buff, so what? Cast it again if you need to.
   
   
3. I'm assuming intelligent players. That is, I'm assuming any real-world player is taking into account party composition after the roughly 1 year or more it takes to ever be fighting a Marilith. Yeah, obviously, if your party is one melee guy + 3 ranged guys, they're not going to use the Grapple + Prone trick. Obviously, you don't use Polymorph on your most powerful melee ally. Obviously, if you are using Tenser's Transformation, you aren't rushing into the marilith's face with 8 STR and a mundane longsword. I don't think things like that need to be said.

Your point 2 is the thing that your badly ignoring. If a caster is always behind on damage behind on hp & always behind on ac they need to either reliably be completely indispensable when they step out or they need to have the significant improvement of the situation they bring to the table to last for long enough to have more impact than a couple crits would have.

Look at it from the WoW raid analogy point of view. More than one of your examples of a great buff actually hinder the party & would get the caster added to a do not invite list if done regularly. Out of the few that could improve things the effect is so small that almost any other class is likely to be more valuable to the raid given how far they lag the rest of the time. Hanging your hopes on a highly specific party composition to rescue a boat anchor of a strategy for many other party makeups only works if there are a bunch of other spells that do something amazing for other highly specific party compositions & that frankly is not even slightly the case.

 

[FrogReaver]

Your point 2 is the thing that your badly ignoring. If a caster is always behind on damage behind on hp & always behind on ac they need to either reliably be completely indispensable when they step out or they need to have the significant improvement of the situation they bring to the table to last for long enough to have more impact than a couple crits would have.

Look at it from the WoW raid analogy point of view. More than one of your examples of a great buff actually hinder the party & would get the caster added to a do not invite list if done regularly. Out of the few that could improve things the effect is so small that almost any other class is likely to be more valuable to the raid given how far they lag the rest of the time. Hanging your hopes on a highly specific party composition to rescue a boat anchor of a strategy for many other party makeups only works if there are a bunch of other spells that do something amazing for other highly specific party compositions & that frankly is not even slightly the case.

IMO. High level casters are already generally stronger and more versatile than martials in combat. And they have the ability to actually do things out of combat.

 

[tetrasodium]

IMO. High level casters are already generally stronger and more versatile than martials in combat. And they have the ability to actually do things out of combat.

That requires spells to be prepared & be relevant to the situation. Without even one example of "things" there's not much to go on, but xge devotes quite a few pages to ways noncasters can use the free tools most everyone can get proficiency in to do specific "things" that would otherwise take a spell a caster probably won't have prepared