Your math analysis is dumb. It's a 3rd level spell lot which you don't seem to be taking into account versus an at will attack. Would you spend a 3rd level spell slot to do 6% more average damage? If you roll high and it happens to miss its save, it's using his Legendary Resistance. So don't even pretend the 60% is happening. It has an automatic trump card for the off chance you roll high damage and it misses its save. Take it in. You roll maximum damage, 48 points...all 6s, you have Yahtzee on the roll. Your ecstatic. It rolls it save. It rolls a 1 or 3 and misses. You're thinking....this is awesome. I got lucky and nailed the dragon for a huge hit. DMs says it uses one of its three Legendary Resistances. You do 24 points. It's definitely higher than the cantrip. But about the same for a level 10 Great Weapon Fighter or Archer that hits twice.
It takes all of that to do 24 points of damage. If you were equally lucky with your cantrip. You roll a 20 and you get Yahtzee on your double dice. You do 40 points of damage at level 10.
Like I said, there is no mathematical analysis you can do to prove that a 3rd level slot fireball with a save is a better expenditure of resources against a Legendary Creature that will take guaranteed damage from an unlimited resource fire bolt. It's a losing argument on your part for many, many reasons.
I stated earlier that Fireball was better than Fire Bolt
assuming the caster's primary concern is doing damage as fast as possible without regard for using up their resources like spell slots, in other words damage per action, not damage per slot. When you are in a combat where you are expecting to be dead in a few rounds if you don't take down the enemy, you pull out all the stops and throw everything you have into defeating the enemy before it can kill you. That 3rd level slot you save by casting Fire Bolt won't do you any good once you are dead.
And since you seem to be having trouble understanding the math, I'll break it out for you.
Fireball does 8d6 damage. A d6 averages 3.5, therefore the average of 8d6 is 28 points. There is no attack roll for Fireball, so there is no chance of a miss, and likewise no chance of a critical hit. In this situation with your DC 16 and the dragon's +5 save, there is a 50% chance it saves for half damage, and a 50% chance that it burns a legendary resistance to save for half damage. So in 100% of the cases, the average damage will be half of 28, or 14 points of damage on average per casting (100% * 14).
Fire Bolt at L10 does 2d10 damage. A d10 averages 5.5, therefore the average of 2d10 is 11 points. A critical hit does twice as many dice of damage which would result in 4d10 damage (not just doubling the result of 2d10), which averages 22 points. With your +12 bonus against AC 18, you have a 5% chance of landing a critical hit for an average of 22 damage, a 70% chance of landing a hit that is not a critical for an average of 11 damage, and a 25% chance of missing for 0 damage (no matter how many times you claim Fire Bolt is guaranteed damage, it is not guaranteed to hit and therefore is not guaranteed to do damage on every casting). (5% * 22) + (70% * 11) + (25% * 0) = 8.8 average damage per casting, which includes factoring in critical hits and misses.
14 damage (Fireball) is 59.1% more than 8.8 damage (Fire Bolt). So yes, at level 10 the Fireball is doing just shy of 60% higher average damage than the Fire Bolt. I would agree with you if you were saying that Magic Missile is a better use of the 3rd level slot than Fireball since it is a guaranteed hit for a total of 5d4+5 damage (17.5 average), but the discussion was originally Fireball vs. a cantrip.
The odds of landing that critical yahtzee fire bolt you mention is 1 in 200,000. (5% chance per attack to score a crit, and then a 1 in 10,000 of rolling 4 10s on 4d10 crit damage). If your wizard cast fire bolt once a round every round, you would expect to see that 40 point hit occur once in 200,000 rounds, or once in 13 days, 21 hours, and 20 minutes of casting around the clock. The odds of maxing out the fireball for 48 damage are less (1 in 1,678,616), but the odds work out the same on the opposite end of the spectrum for rolling minimum damage, with the fireball much less likely to roll a 8 for damage then the 4d10 rolling a 4. The odds of rolling the extremes don't change what the average damage for a roll is, it just impacts how much a roll is likely to vary from the average (both above and below the average equally). And the odds of rolling that yahtzee crit are already included in the average damage roll as part of the 22 average damage on the 5% chance of a crit.
The rules are basically saying that for some reason the poison and cold from a dragon's breath are not something you can dodge, but their' saying the acid and fire can be dodge? It makes no sense and is dumb. Doubt we'll ever agree otherwise.
The we can agree to disagree. I don't find the Con save for poison and cold breath any less realistic than the idea that a rogue could somehow stand naked in the middle of a house size blast of fire with no cover and without moving out of the area, and somehow be completely untouched. By having some breath weapons target Con instead of Dex, it means the a rogue will need to pay attention to what type of dragon they are fighting, and it leaves an opening in the game design space for abilities like the 3.5 "mettle".
Like what? What was available? You can't buy magic items in this game. So don't pretend that was available.
If getting the magic items you want isn't possible in your game, how did your wizard get a Staff of Power, and why can't the player of the martial do the same thing to get the GM to give them the substantially less valuable Boots of Flying?
We used Fire Shield for one person or you forget the low number of spell slots and inability to make scrolls to boost spell slots. We also had Protection from Energy up on the cleric. And fly. The two spells I'm complaining about. Because once we had those two spells up, we were done casting concentration spells. Both are concentration.
If you really want a devastating spell combination while conserving your slots, have the cleric cast Spiritual Weapon and send it against the dragon, then you use you use a level 5 slot to cast Wall of Force as a sphere around the dragon (can be cast in mid-air and has no save) and the spiritual weapon and then leave the line of sight to make it harder for the dragon to target you with lair actions (freezing fog can only be targeted where the dragon can see, and falling ice can only target creatures the dragon can see). The dragon can do nothing to escape the Wall of Force until either you lose concentration (up to 10 minutes) or willingly drop it, and it can do nothing to stop the Spiritual Weapon from attacking for its full duration (if cast as a L5 spell it is doing 3d8+Wis per hit, and the cleric can be benefiting from bless on the attack rolls). If the cleric's hit chance is as good as yours, you are looking at likely 7 hits doing a total of 21d8 plus 7 times their wisdom modifier damage for a total of somewhere in the neighborhood of 120 damage. Depending on how your DM rules, the cleric may be able to recast Spiritual Weapon inside the sphere since Wall of Force is worded that nothing physical can pass through it, but the spiritual weapon can appear anywhere within range. If the DM rules that the spiritual weapon can't be summoned inside the sphere, I would have issue with them if they also ruled that the dragon could still use lair actions from within the sphere. Even if you only get one cycle of damage like that, you will have done over half the dragon's hit points in damage with little risk to the party. If you can recast Spiritual Weapon inside the sphere, then the dragon will be dead long before the duration of the sphere ends.
Parties that don't work together against powerful creatures die. The wizard cannot stand up to a round of dragon attacks along with a breath weapon. He cannot do enough damage to take it down alone (which I agree he shouldn't). You can't buy magic items in this game like fly potions or scrolls. So you have to cast on the fighter or martials or they sit on the ground. Javelins past 30 feet have disadvantage. Dragons move 80 feet and full attack.
Stop pretending like we're somehow making mistakes. The only thing you can say is we didn't bring enough archers. Sorry, the martial players in my group didn't make an archer thinking the game would be set up like this. In previous editions of D&D you could have fun making whatever type of martial you wanted because you didn't have to have to ranged attacks. The casters could get the martials into action with fly without gimping themselves defensively and offensively.
Martials without decent ranged attacks had the same issue in earlier editions. A 3.5 adult white dragon was over twice as fast (fly 200'), had access to Flyby Attack, Wingover, Hover, and Snatch, and could cast spells as a 1st level sorcerer (mage armor and shield were a prime choices). They could strafe with their breath weapon just like a 5e dragon can, and could get much farther away in between attacks. If they wanted to, they could do a Flyby, use Snatch to grab their target after they hit, use the rest of their movement to fly away climbing as high as they could, then drop the target as a free action at the end of their turn. Even if a wizard cast fly on the martial, the martial would be 140'-160' slower than the dragon. They even had both Spell Resistance and DR 5/magic. That was at a CR 3 lower than the 5e adult white, so would have been encountered a couple levels earlier in the PCs career. And if you want to look at 4e, the popularity of immobilization, slow, and forced movement effects resulted in many situations where PCs couldn't bring melee attacks to bear. Fly in 4e was a L16 wizard daily personal ability with sustain, and Mass Fly was a L22 wizard daily with sustain, so wizards weren't throwing fly on their martial companions until epic levels. The vast majority of my play experience in earlier editions was with melee PCs, which is where I learned the value of having a ranged attack option. I played a melee warlord from 1st to 30th in 4e, and my two longest running PCs in 3.x were a fighter built as a spiked chain wielding gladiator and a duskblade.
I never said that martials had to be archer builds. What I said is that even a melee martial should probably carry a bow or crossbow as a backup weapon, because even if their Dex bonus is 4 lower than their Str, the bow gives them a better chance to hit against ranged targets that are far enough away that they couldn't just move and attack. At level 10 with a +0 Dex, they would be +4 to hit out to 150', and disadvantage to 600'. With a thrown weapon they would be at +8 to hit instead, but beyond 30' they are at disadvantage and can't attack at all beyond 120'. Against an AC18 dragon, the martial would have a 35% chance to hit with the bow (needing 14+), or a 30% chance to hit with the javelin with disadvantage (two rolls needing both 10+). If the dragon was between 121' and 150', the difference would be 35% chance with the bow vs. 0% chance with the javelin, and from 151' to 600' you would still have a 12% chance to hit with the bow. 35% may not be great and 12% is pretty bad, but it is better than nothing at all. With absolutely no change to their class, attributes, or feats and with the investment of a whopping 50gp and 4lbs of weight their ability to contribute in ranged encounters improves. If they had already invested anything in Dex to get the benefits on initiative, skills, and Dex saves, their ability with a bow would be even better.
Did you contradict yourself?
Nope. I said that you should have the choice to create what you want. But I also said you should have to deal with the consequences of that choice and not expect others to make sacrifices to deal with those consequences without you having the courtesy to ask them first. Not all options are equally good in all situations. That's the way it is in the game, and that's the way it is in real life. You are equally free to major in human services or computer engineering, but don't expect the jobs to offer the same pay, and don't expect someone else to make up the pay difference if you choose the lower compensated career path. It isn't an unreasonable level of metagaming to understand that heroes in D&D will likely have to deal with things like melee combat, ranged combat, magic, traps, and flying monsters at various points in their career, so thinking ahead about how your character can survive and contribute to the success of the partyis beneficial, and working with the other players during character creation on how the party as a whole will handle those occurrences is a good thing.
I'm advising never make anything without a ranged weapon that is good over 60 feet. So pretty much a crossbow or bow user. Don't even bother making strength-based characters any longer using swords and axes. Only Dex-based characters or you'll be screwing your casters as they have to figure out how to get you into battle. If you're an archer or crossbowman, you'll never have that problem. That's my advice to you if you never want to be an inconvenience to your casters due to concentration.
Having a ranged option available is good advice. Why is suggesting a martial have a ranged option any worse than suggesting a caster pick spells that are a mix of range and melee, or single targets and AoEs? And just because you have a ranged option doesn't mean that has to be your only option or even your primary option. Archers and crossbowmen have their own issues, they have to worry about running out of ammunition and having melee attackers in their face giving them disadvantage so they should probably make sure to carry a melee weapon just in case. Plus going with a lower strength in favor of dexterity means less carrying capacity and frequently lower armor class.
We don't metagame. We make characters to have fun.
And seeing as how you are posting here about how you aren't having fun, I see how well that is working out for you.
Parties that don't work together, die in our campaigns.
No. We couldn't have. It is not easy at all to find level 10 archers. You think finding level 8 or 10 characters is easy? One breath weapon for low level archers, they're dead. Do you think the dragon is going to dumbly sit there and allow itself to be peppered with archery or fly up an destroy it with breath weapon and then fly on. I don't know if you have a fought a dragon yet, but being able to move 80 feet a round and full attack or breath weapon along any point does not make them easy to control. They have superior mobility to any character in the party.
You are right. Team work is critical. A party that works well together is greater than the sum of its parts. And parties where the members both work well together and have complementary abilities to minimize weaknesses that their enemies could exploit is even better.
If the dragon is flying moving 80' with melee attacks in the middle, then it should be around 40' away between attacks. In that case, it won't have targets close enough for tail attack or wing attack legendary actions. If it is close enough for those actions, then it is also close enough to be vulnerable to reach and/or thrown weapons. If it is making a full attack, then it is close enough that when it moves away it will draw an attack of opportunity. The dragon's freezing fog is big, but smaller than the breath so if the party has spread out to reduce exposure to the breath, it will only get one or two people with the fog. There are some disadvantages to spreading out, but letting the dragon hit multiple targets with its most powerful attack at no additional cost will drop PCs quickly. I've said many times that yes this is a brutally hard fight, but part of that is that this particular fight is not one that your party is well suited for. That happens, I don't think I've ever seen a party that didn't have something that they had trouble dealing with.
Yes. We interacted with her. She gave us some nice scrolls. I added quite a few nice spells to my spellbook.
To our knowledge use of a scroll does not obviate concentration. So even if you cast a spell off a scroll, you're still stuck concentrating. All it does is save a spell slot. Unless of course you know differently. If you do, let me know.
Then your party didn't get what they were supposed to get from her.
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She should have given you a
ring of cold resistance and two
arrows of dragon slaying that she crafted, as well as being a source for extensive knowledge of the dragon and its capabilities. I'm sure having another party member who was taking half damage from the breath weapon, freezing fog, and any other cold creatures and environmental effects would have been useful. If there is even one person in the party who is reasonably competent with a bow (maybe a rogue or even a bard), the arrows will give them a decent chunk of extra damage. The arrows do an additional 6d10 damage (DC 17 Con save for half) to the dragon and their magic isn't expended if they miss. I assume the dragon will make its save, but even making the save the arrows will do an average of an extra 16 damage each on top of any damage the attacker would normally do. And if the attacker was a martial with extra attacks, both arrows could be fired in a single attack action.
Also if the DM felt the party was outmatched and wanted to give them something to help balance the encounter, this would have also been a perfect opportunity to do it since the NPC was already established as being capable of producing magic items.
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