How do I maximize the damage of a single, unarmed attack?

Question

I've noticed that monks favor many, smaller attacks which grow to a set limit of strength after a period of time, but I was wondering if you could somehow get a different build setup that favors a few, stronger attacks, especially after seeing the Unarmed Combat fighting style in the Fighter class. Please avoid the use of Unearthed Arcana, as I'd like to stay as official as possible.

Additionally, the focus is on races, classes, subclasses, items, and associated base combat information that do not need gold investment or preparation, and excludes spells and preparation that lasts longer than 5 in-game minutes, if at all possible; the idea is to not prepare for a day just to make a single hit, but to be able to reliably deal high damage in short instances with just fists alone. There is one exception that I'll make to that rule, and that's if the preparation's effects lasts for an extended period of time, at least to the tune of several days.

Assume you have 20 levels to invest, but no gold. The damage shouldn't be based on limited resources or items as well.

Answer 1

Your title suggests one hit, but your description adds

the idea is to not prepare for a day just to make a single hit, but to be able to reliably deal high damage in short instances with just fists alone.

In that case, let me suggest

The Pugilist

Custom Lineage, Darkvision, Skill Expert +1 STR, Stealth (because Surprise), Athletics (expertise because grapple/shove)

14 Str, 14 Con, 13 in Dex, Wis, whatever in Int and Cha (+2 Str)

Fighter 1, Unarmed Fighting (d8 since we aren't wielding any weapons), Perception, Intimidation (your choice), Second Wind

For equipment, two handaxes (for throwing) and Chain mail. When you get some money, switch out the handaxes for javelins (for range). Dump the chain mail when you get Unarmored Defense, as we can't get the bonus Monk attack when wearing armor.

Monk 1 (level 2), for Martial Arts bonus action unarmed attack

Fighter 2-5 (level 3-6), Action Surge, Champion, Crusher feat (+1 STR), Extra Attack

Barbarian 1-3 (7-10), Rage, Reckless Attack, Path of the Beast (extra attack with claw - note, you probably have to use the claw at least once (d6 slashing instead of d8 bludgeoning) and gain one extra claw attack.

Fighter the rest of the way for Extra Extra Attack (F11, class level 15) and feats, Slasher (+1 Dex), ASI CON, Sentinel, Resilient Wisdom, ASI STR, or whatever suits you.

When you consider the attacks are not magical, this becomes less and less effective as more enemies have resistance to non magical attacks. Ideally you would get two common, one hand (each) Eldritch Claw Tattoos. That or dip back into Monk for 5 more levels, but that would add some redundancy, a few features, and delay the extra fighter feats and Extra Extra Attack.

Attacks at level 10, (sustained with Reckless Attack, no Rage)

1. Unarmed d8 bludgeoning +STR
2. Unarmed d8 bludgeoning +STR (Extra Attack)
3. Bonus action (from Martial Arts), Unarmed d8* bludgeoning +STR

* You can substitute your Martial Arts die (d4), but you don't have to :)

DPR ~22.38 (baseline 16.1)

With Action Surge, Reckless Attack and Rage (probably 2x per day)

1. Unarmed d8 bludgeoning +STR +Rage
2. Unarmed d8 bludgeoning +STR +Rage (Action Surge)
3. Unarmed d6 slashing +STR +Rage (claw) (Extra Attack)
4. Unarmed d6 slashing +STR +Rage (claw) (Extra Attack, Action Surge)
5. Unarmed d6 slashing +STR +Rage (claw) (PoB)

(Bonus action used to Rage)

DPR ~43.88 (baseline 18.77, this looks like a lot, but at 11 baseline goes to 27)

With Reckless Attack and Rage (subsequent to Action Surge)

1. Unarmed d8 bludgeoning +STR +Rage
2. Unarmed d6 slashing +STR +Rage (claw) (Extra Attack)
3. Unarmed d6 slashing +STR +Rage (claw) (PoB)
4. Bonus action (from Martial Arts), Unarmed d8 bludgeoning +STR +Rage

DPR ~35.10 (baseline 18.77)

Considerations

You may score at least one crit (47%), especially on Action Surge (65%). If that's a bludgeoning attack, that will benefit your off turn reaction attack from Sentinel (since you can't use Reckless Attack off turn, but Crusher will give you advantage until your next turn on a crit). Crusher also gives you some mobility options, as you can move an enemy with 5' reach and move away without provoking. It also gives you some good options for pushing enemies into hazards. If you crit with slashing damage, your enemy will have disadvantage on its attacks until the start of your next turn. Any hit with slashing damage can reduce the target's speed by 10', once per turn.

This is not a phenomenal damage dealer, but enough to beat the baseline. At least with respect to melee, you cannot be unarmed. This could work well with a city adventure with strict laws or any adventure where you are captured and stripped of your belongings.

The ability to throw weapons will help maintain rage as well as give you some options when enemies are not in melee range. You won't be using any object interactions normally, so drawing and throwing one thrown weapon will be an option. At Fighter 10, you could choose Thrown Weapon Fighting to give you a damage boost as well as be able to throw two weapons using Extra Attack, three at Fighter 11.

This build cannot boost unarmed strike damage with Great Weapon Master or Sharpshooter, so it's going to be behind builds that take advantage of those feats. On the other hand, we get a bonus action attack from Monk, and an extra attack from Path of the Beast - Claw while raging, so that helps balance the missing damage boost, as well as not taking the attack penalty, so you'll hit more often, especially when using Reckless Attack.

This character also has expertise in Athletics, making them very good at grapple/shove or grapple drag, so that will open up a lot of options and make you hard to pin down.

Armor class is a weak point. In order to get the extra attack from Martial Arts, we cannot be wearing armor, so even with Unarmored Defense from two classes, they don't stack, so we just get the best of either. Boost CON and consider boosting DEX.

Sustained damage is good and probably two to three rounds per day, depending on short rest frequency, very good, with a boost to sustained from Rage for the rest of the combat.

Answer 2

Battlemaster Fighter, 78 damage / round

At the outset, let me state your request is a little contradictory: if you want to spend no resources that are in any way limited, then by necessity what is left will apply to every attack, no matter how many you make. Whereas if you want to maximize only a single attack, you do so with effects that by definition would not apply to all attacks. So, I interpret "no resources" in the sense that it should be a build that can deliver a given amount of damage for most attacks, and will call out the share that is the "no resources" baseline of what works for every attack you expect to make.

One good option is the Fighter, in particular the Battlemaster. Battlemasters get Superiority dice, and those can be added to all kinds of attacks, both for extra damage and also for nice additional effects. You get 6 d12 on level 20, You gain them back each short rest, and get an extra one each time you roll initiative. That is 7 d12. With the average fight taking 3-4 rounds and you having 4 attacks thanks to extra attack each round, you can apply them to maybe half your attacks (you can only apply one per attack).

Race: Half-Orc for Savage Attacks or Bugbear for 2d6 extra damage on surprise attacks are good options. Surprise is much more powerful, but circumstantial.

Example Build: Level 20 Half-Orc Battlemaster

• Initial Strength: 15+2 from Race = 17.
• Level 1: Fighting Style: Unarmed Fighting, for d8 base if empty handed
• Level 3: Battlemaster. For example, Trip Attack, adds d12 to damage and opponent must save or be knocked down. Add others to season.
• Level 4, Tavern Brawler Str+1, proficiency with unarmed strikes
• Level 6: Str+2 for Str 20
• Level 8: Crusher, Con+1, bludgeoning can push 5', crits yield advantage
• Level 10: Magic Initiate for hunter's mark, can be cast on first turn for extra d6 to damage, this part only works for one fight

Average Raw Damage per attack: 4.5 (d8) + 5 (Strength) + 6.5 (d12 Superiority die) + 3.5 (hunter's mark) = 19.5 damage, Average Raw Damage per Round: times 4 attacks = 78 damage

Without any resource use, Superiority and hunter's mark drop, leaving 9.5 damage per attack (no better than what a monk would have on level 20), or 38 per round.

If you want a nova round, you have two Action Surges at level 20, each of which lets you repeat the entire attack sequence, for a total of 234 damage in one round.

(I ignored the light uptick from criticals that cause advantage for subsequent attacks, as that comes only to play with expected damage and has a minor damage contribution from higher chance for criticals).

Maximum Damage on Single Attacks

A classical chassis for nova damage bursts on single attacks would be a Paladin. There are various "Smite" spells that only require a melee weapon attack, and an unarmed strike is a melee weapon attack, so they apply. As you have a lot of spell slots by level 20, and a typical fight takes about 3-4 turns, and a typical adventuring day has maybe 3-5 combat encounters, and you have 15 spell slots, even with extra attack you can apply some smiting goodness to at least half of your attacks, all on days with fewer fights.

Assuming a similar feat progression as above (stretched a bit as no ASI on level 6 and 10) a paladin (Oath of Vengeance) would be able to use their Vow of Enmity to attack with Advantage (for a crit chance of about 10%). In the second round, they could add on hunter's mark, if desired. I omit the Oath capstone feature, as it only works once a day. If you use it, Oath of Conquest might be better, you give up advantage on attack, but crit on 19 or 20 for nearly the same chance, plus you get one more attack with the attack action.

Raw Damage for Single Attack: 4.5 (d8) + 5 + 22.5 (5d8, divine smite) + 3.5 (d6, hunter's mark) = 35.5 + ~ 3 from 10% critical chance = 38.5

This is less sustainable, as the higher level spell slots will run out soon. Without resources, 9.5 damage as above.

Answer 3

You can reliably get 92.21 DPR with unarmed attacks, or you can deal 34.99 damage on one attack per turn at the cost of 55% of the DPR

The Approach

Since the request is to maximize the damage of one unarmed attack, I focused the first build on exactly. Certainly it would be better damage-wise to use features that give extra attacks to gain more damage per round, which you will see in the later builds.

Additionally, those later builds break the "no spells" rule (while still being sustainable), but do even better damage while still being usable every combat.

The Character

Our character is a level 20 half-elf {8,18,14,8,14,8} with the following classes:

• Fighter (Battle Master) 3 -------------------- for Unarmed Fighting and Combat Superiority
• Monk 1 ----------------------------------------- for Martial Arts
• Barbarian (Zealot) 3 -------------------------- for Reckless Attack and Divine Fury
• Ranger (Hunter) 3 ---------------------------- for Colossus Slayer
• Druid (Circle of Spores) 2 -------------------- for Symbiotic Entity
• Cleric (War Domain) 8 ------------------------ for Elven Accuracy, 1 ASI, and Divine Strike

The Damage

Here are all of the contributors to our damage:

• 1d8 bludgeoning --------------------------------- (base via Unarmed Fighting)
• 4 bludgeoning ------------------------------------ (Dexterity via Martial Arts)
• 1d6 + 1 radiant/1d8 bludgeoning -------------- (either from Divine Fury using a Rage, or Combat Superiority using a number of Superiority Dice; alternating between the two should yield full up time)
• 1d8 bludgeoning --------------------------------- (via Colossus Slayer)
• 1d6 necrotic --------------------------------------- (via Symbiotic Entity)
• 1d8 radiant ---------------------------------------- (via Divine Strike)
• 4d8 + 1d6 extra damage ------------------------- (14% criticals via Reckless Attack and Elven Accuracy)

Total: 28.57 damage on one attack

For damage per round, we get a second attack via Martial Arts, but it doesn't benefit from Divine Fury/Combat Superiority, Colossus Slayer, or Divine Strike yielding:

41.71 damage per round

Spells with this build

With the above build, we can also sprinkle in some spell buffs to help our damage a bit. However, I will go into a spell focused build later that does even more damage per attack.

Our characters is a level 10 spellcaster, and the best spell to boost our damage is spirit shroud for an extra 1d8 or 2d8 (depending on spell slot) per attack. Twice per day we get the 2d8 (25% of the time), and six times per day we get the 1d8 (75% of the time).¹

Factoring in critical hits, we get a boost in damage of 6.43 damage per attack.

Total: 34.99 damage on one attack

Like before, our second attack from Martial Arts give us:

54.56 damage per round

¹ If you have more than 8 combat encounters per adventuring day than the damage totals diminish, but that is a very uncommon occurrence at most tables

Adjusting for Extra Attack

If you want to adjust this "with spells" build for maximum damage per round, here is the adjusted classes:

• Fighter (Eldritch Knight) 12
• Monk 1
• Druid (Circle of Spores) 2
• Cleric (War Domain) 5

Our new damage effects are

• 1d8 bludgeoning
• 5 bludgeoning
• 1d6 necrotic
• 2d8 or 1d8 from spirit shroud
• 1d8 + 1d6 extra damage (only 5% criticals now)

Total: 19.31 damage on one attack

...but all 4 attacks benefit from all of the damage modifiers totaling:

77.23 damage per round

All in on spirit shroud

A high level spellcaster gets access to higher level spell slots for spirit shroud that can boost damage further. Here is a build that leverages those high level spell slots:

• Fighter 1
• Monk 1
• Druid (Circle of Spores) 2
• Wizard (Bladesinging) 16

Now that we have much higher level spell slots for spirit shroud we can push beyond 2d8 damage per attack. With our 7th and 8th level slots, we hit 3d8, and with our 9th level slot, we hit 4d8. Additionally, we should use that 6th level spell slot on tenser's transformation instead of spirit shroud for a bit more damage during that combat.

Overall that makes our average damage from spells 2.57d8 in 87.5% of combats, and 2d12 in 12.5% of combats.

• 1d8 bludgeoning
• 5 bludgeoning
• 5 bludgeoning (Intelligence from Song of Victory)
• 1d6 necrotic
• 2.57d8 from spirit shroud (87.5%)
• 2d12 from tenser's transformation (12.25%)
• [2d12 or 2.57d8] + 1d8 + 1d6 extra damage (5% crit)

Total: 30.74 damage per attack

...and 3 attacks totaling:

92.21 damage per round

Conclusion

All of these build are highly connected to the number of combats per adventuring day due to their reliance on scaling spells, so I figured I'd provide a table that shows how they do if this number varies. Here are those DPR values:

Encounters per Day	War Cleric	Eldritch Knight	Bladesinger
8	54.56	77.23	92.21
7	54.93	77.90	93.45
6	55.42	78.80	95.10
5	56.10	80.06	97.41
4	57.13	81.95	100.88
3	58.85	85.10	102.45
2	62.27	91.40	104.81
1	62.27	91.40	111.90

Additionally, here is the Bladesinger's DPR per level at 8 encounters per day if you level with the below order:

Fighter 1/Monk 1/Wizard 6/Druid 2/Wizard 16

Levels	DPR
1	7.725
2-5	15.45
6	17.45
7	20.99
8	33.26
9	35.03
10	47.83
11	53.15
12	57.92
13-14	61.46
15-16	66.58
17	70.13
18	82.13
19	87.44
20	92.21