Also losing to warlock in utility and at-will damage
Sword and Board Fighter -> 21
Greatsword Fighter with no Feat -> 24
Totem Barbarian with no Feat -> 25
Paladins (same damage as Fighter, has weaker utility spells)
Rogues -> 18
It is always bad to simply add up Rogue damage. A smart rogue has an offhand weapon to get 2 chances to land sneak attack damage dice (at the risk of not being able to disengage), which is a massive increase in actual damage delivered. (They also get a small edge from the fact that damage dice > static damage due to crits)
Whenever there is such a significant accuracy difference between characters, you should pick a model AC. Personally I often pick 18, as it is a credible AC to run into at both low and high levels, and using -5/+10 feats is a bad plan at that AC at almost any level.
I guess it depends on what you want from the Dodge action. Do you want to take no damage, or do you want to waste the enemies attack. If you want to take no damage, them attacking an ally is a similiar result.
This is a group game. So redirecting damage to someone else is worse than not taking it yourself.
And, as noted, it is
really expensive. You are burning a lot of potential damage in order to not be splattered, and you have to do it preemptively.
Again, sure, spells are great. Monks aren't spellcasters though, and there is a fundamental difference in the intent of Stunning Strike vs a save spell like Hypnotic Pattern.
Hypnotic Pattern is being used to take some group of enemies out of the fight, even if half the enemies succeed in their saves, the spell is a success. It is also a 3rd level daily ability.
It is a 2x per day ability on level 5 wizards/bards or 2x per rest abilty on level 5 warlocks.
There are multiple possible uses for stunning strike. One of them is to run in and stun a bunch of weak foes. The other is to hammer one big foe.
I'm noting that stunning strike isn't that effective at a bunch of weak foes.
The Monk's Stunning strike barrage (spending multiple ki to get one target to fail) is meant to take a single enemy out of the fight, and is recoverable on a short rest. And, it might come to pass that they only need to spend 1 ki to pull it off, but if the enemy succeeds once, they still have to succeed at least two more times. That is a big difference.
I thought I covered that?
Suppose you are a level 8 monk fighting an Aboleth (CR 10 legendary foe). It has a +6 con save and 3 legendary resistances and 17 AC
You have 14 wisdom and +3 proficiency for a DC 13 stun (not great, not crappy). It needs a 7+ to save, or 70%.
Your Dex is 20, so you have a +8 to hit, and hit on a 9+ (60% chance). You flurry and land 2.4 blows (1 Ki). You stun each time you hit, and burn 2.4*.3=0.72 legendary resists/turn at the cost of 3.4 Ki, or 0.21 legendary resists/ki.
You keep this up for 2 rounds (6.8 Ki), then burn the rest on stunning strike (1.2 more) over the next 1 or 2 rounds. This is 6 stunning strikes, for 1.8 legendary resists soaked.
A pure caster has a saving throw DC of 16 at this point. A cast of banishment requires a 12+, so 45% chance of passing. They'll have at least 2 level 4 slots, burning 0.9 legendary resists over 2 turns.
The caster can also web (Aboleth has no effective ranged options, and crappy strength)
If banish lands, the party gets to set up a readied-action ambush, after cleaning up any "trash" allies of the Aboleth.
Interesting you chose level 6, a spot where the fighter gains an extra feat so you could have the dual-wielding feat. Back level 5 your fighters damage was 3d6+12 (22.5) or 3d8+9 (21.5) both of which were lower than the monks (24.5), heck, even the difference you list is pretty small the BM is only doing 25.5, a single point better.
Sure, but the level 5 fighter has 10.5 healing/short rest while the (open hand) monk has 0. At 6 the fighter has 11.5 healing/short rest on bonus action, while the open hand monk has 18 per long rest on action.
I have no idea how you think the Fighter's AC is better across the board. Light Armor with the Feat is 17, same as the Monk. Medium Armor is likely a Breastplate, so also 17 same as the monk.
Are we talking a 16 dex/16 wis monk with crappy con? Then at 6 the monk has 17 AC as does the fighter.
If the monk wants HP, they are going to probably lose 2 points of wis for it.
The only way you are getting superior is to have half-plate or full plate (18 and 19 respectively) And since you claimed 1 through 10, the monk is going to reach 18 AC by 8, and they had the same 16 AC as your dual-wielder at level 1 (actually, with light armor you would have started with leather, giving you an AC 14 and inferior to the Monk)
The fighter, if human, could have both 20 dex and DW feat for 18 AC at level 6, and 16 dex/DW + leather for 15 AC at level 1 (buying studded using cash-based gear is also an option, for 16 AC; studded, while upgraded armor, is cheap upgraded armor).
Overall, I'm not trying to say the Battlemaster is weak, but some of these arguments seem to be not taking into account just where the monk actually stands.
But if the argument is "Monks are weak because Fighters can get magical platemail" when magic items are not assumed part of the balance, is that something we should fix by fixing the monk, or by giving the monk items to increase AC?
If the problem with monk damage is more than they don't have access to Great Weapon Master, a feat generally considered overpowered to a degree, is the fix to increase monk damage or to give them access to an equivalent feat? When again, feats were not a considered part of class balance during the design process.
The issue seems to be less that the monk was poorly designed, and more that when the designed all the extra bells and whistles to make people more powerful, they forgot to add some whistles for the monk. Which means we need to focus on homebrewing Magic Items and Feats, not Monks.
The issue is that the resources to make a Monk more effective are expensive (attunement, rarer) or absent (feats).
I mean, Tavern Brawler could have stated "when you hit a creature with an unarmed attack, you can make an attack with an improvised weapon". They it would be as much of a feat tax as PAM/XBE is.
Making a good monk feat is hard without it becoming a feat tax.
And bracers of defence are great for monks, but they are +2 and attunement. A ring of protection (+1 AC and saves) is equivalent, and attunement-free magic armor is also in competition.
Monks don't use mechanics that overlap much with other classes (other than weapons), so items tend to be either monk only, or useless to the monk.
I mean, "Staff of Power" -- if it wasn't caster-only, it would rock for a monk (even without the spells).
Baseline, monks are a bit behind other damage dealers. Adding feats and items, they fall further behind. Their defence is also a bit behind, and Ki-based defence eats their damage.
Possibly they should best be compared to other half-casters (Paladin and Ranger); if you look at spell points, monks basically get what you'd expect a per-short-rest half-caster would get in spell points, but as Ki. And then if you look at the 4E monk Ki costs, they are similar to spell point costs.
Viewed that way, we campared to a sword+board strength-paladin.
At level 6, the strength paladin has 18 Str, Plate+Shield (20 AC), 14 charisma (+2 to all save aura), deals 2d8+12 (21) damage at-will, and has 14d8 (63) of smite-damage from spells (can be traded for other spells) per day.
The 2H Paladin is 18 AC, deals 4d6+8 (24.67) at-will, and has 14d8 (63) of smite-damage from spells.
The PAM Paladin is 18 AC, deals 2d10+1d4+12 (2.1+11+2.5+12=27.6) damage at-will at 1 lower accuracy (unless human), and has 14d8 (63) of smite-damage from spells.
The Monk has similar accuracy, 18 dex 14 wis for 16 AC, deals 2d8+1d6+12 damage at-will (24.5), and has 6d6+24 (45) of short-rest flurry damage (can miss, be traded for defence or stuns).
Attacking 18 AC normal damage is worth about 1/2 smite-damage (due to misses), so with 2 short rests the monk's flurry damage is only slightly more than the paladins (and has to be spread out over the day). On lower AC "trash", flurry damage is more useful.
A +1 weapon boosts paladin damage output and accuracy (percentage wise) more than the monk.
The paladin can cast crazy useful spells like "bless" instead of a 2d8 (9) smite. The monk can convert 7.5 damage into a stun, or 15 damage into a one-turn dodge.
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I mean, the monk is within a "margin of error" of the comparisons. 10% here, 20% here. But it almost always comes up short in the raw numbers, has little in the way of "going the extra mile".
In the hands of a non-optimizer, you probably aren't doing a 16/16 build and carefully using open hand to dash in-out by turning off reactions. In the hands of an optimizer, the player could play that monk, or the PAM human paladin, deal 86% of a monk's "all out" damage at-will, then turn on mass smites and end boss fights faster than the monk can say "I use stunning strike for the 5th time".