Can unarmed strike work with a rogue's sneak attack?

Question

So a situation came up last night where a player with a monk/rogue was flanking (I use the optional flanking rules to grant advantage) an enemy. He was armed with a shortsword, but even with advantage, he missed the attack roll and thus did not get to use his sneak damage.

Since he had taken the Attack action with a monk weapon (shortsword), he could make an unarmed strike as a bonus action, as granted by the monk's Martial Arts feature. He still has advantage on that role since nobody had moved and the attack hit. But then the issue came up; is unarmed strike a finesse weapon? Is it eligible for sneak attack?

I ruled yes and allowed the sneak damage on this attack, but should I have allowed this or strictly should this not have worked?

Answer 1

Strictly by Rules as Written and Intended, no.

By RAW, no. What you ruled doesn't work. Let's look at the important passages from the skills involved.

Martial Arts:

You can use Dexterity instead of Strength for the attack and damage rolls of your unarmed strikes and monk weapons.

Sneak Attack:

The Attack must use a Finesse or a ranged weapon.

While unarmed strikes count as weapon attacks, they are not weapons. It's an important distinction precisely because of situations like this.

Also note how Martial Arts doesn't say that it grants finesse. It could have and it would have been simpler. The fact they felt the need to write it the way that they did suggests that their intent was to keep the Monk Martial Arts skill separate from things like Sneak Attack.

By Rules as Fun, yes.

There's solid logic to your ruling and it gives one of your players an extra little oomph and, more importantly, fun. A ruling that goes against RAW isn't exactly wrong, especially in 5e where the rules talk a lot about the power of the DM.

What to do going forward.

What you should do in the future depends on how your table is run. If you want to stick to RAW or RAI, then you should probably tell the group at the next meeting that after further research you've decided that was a one time thing.

But if you don't mind breaking RAW and RAI a little because it's fun for the table, then there's nothing wrong with this interaction. Just keep in mind that you will be making your PC a little stronger than he's intended to be. Nothing wrong with that though, sometimes that's really what makes a campaign fun!

Answer 2

The Sage Advice Compendium provides a direct, official answer to this question, which requires no interpretation:

Can a rogue/monk use Sneak Attack with unarmed strikes?

The Sneak Attack feature works with a weapon that has the finesse or ranged property. An unarmed strike isn’t a weapon, so it doesn’t qualify. In contrast, a rogue/monk can use Sneak Attack with a monk weapon, such as a shortsword or a dagger, that has one of the required properties.

(Quotation is under the Multiclassing section if you're having a hard time finding it)

Answer 3

Strictly speaking, unarmed strikes are not finesse weapons and cannot be used for Sneak Attack.

Instead of using a weapon to make a melee weapon attack, you can use an unarmed strike: a punch, kick, head‑butt, or similar forceful blow (none of which count as weapons).

So unarmed strikes don't count as weapons. Moreover, the Monk's Martial Arts ability says:

You can use Dexterity instead of Strength for the attack and damage rolls of your unarmed strikes and monk weapons.  

This lets you use Dexterity instead of Strength, similar to the finesse property, but does not actually give the finesse ability. So even if unarmed strikes counted as weapons, they wouldn't count as finesse weapons.

Answer 4

This is one of the times which I look at realistically vs rules lawyer.

By RAW (Rules As Written) since an unarmed strike is
a) not a weapon and thus
b) has neither the finesse nor ranged trait

it would be incapable of accepting sneak attack bonus.

The attack must use a finesse or a ranged weapon. (Basic Rules p. 27)

(Un)Fortunately this is demonstrably untrue as shown in real life.

How so? There are a multitude of martial arts that specifically teach you to strike for vital points to cause the most harm. What is a sneak attack? It is attacking a vital point to do the most harm. Even a non-martial artist could potentially get a sneak attack bonus with an unarmed strike via a "sucker punch" (these tend to be MUCH more effective than a normal punch... i.e. sneak attack damage) a "kidney shot", a throat or groin strike, all of which are more effective if they aren't able to defend themselves properly/unaware of incoming attack (you have advantage).

Attempting a "knockout blow" in boxing could also be considered an attack that would accept a sneak attack bonus (for added realism. After all a 1-hit T.K.O. is possible, and game mechanics wise would require an unarmed strike + sneak attack + critical hit to accomplish)

Answer 5

For some fun, since he is that specific multi-class, you could just make available to your monk the possibility to get a pair of gloves with reinforced knuckles or some gauntlets to count as weapons that have the finesse property.

If a monk wears a pair, the damage from the gloves progress like the monk's unarmed attack (you could even start making +1, +2, +3, martial arts oriented gloves), and the wearer can´t be holding any other weapon in their hands, or maybe trying to attack with a weapon while wearing the gloves gives disadvantage to that attack.

If he ain't wearing them by any reason, he can't use Sneak Attack with his fists (note I didn't say "unarmed attack").

Another option could even be restricting this multiclass Monk/Sneak Attack choice to just be possible with those kind of gloves, and no other rogue usual weapon. Flavor!

If any other class wanted to equip a pair, they just works like clubs, no finesse.

From a coherence point of view, you can hit somebody with your bear hand in a precise and specific spot and knock them out, even kill them. Throat, temple, back ear, and so on. Everybody knows, more or less.

Add a well bandage wrapped protected hand in a glove with some metal, wood or bones in its knuckles, and things gets harsher for foes and more bearable for your hands.

Rogue's Sneak Attack feels like something very suitable: vicious surgical strikes with small tools against weak spots.

I hope some day they will finally add something like it officially, doesn't make much sense to me they haven't yet, the whole knowledge and concept about a martial artist class has evolved a lot from the narrow classic one, something totally understandable putting it in the correct context in its time frame, though.

I would say the Monk class really needs some love.

Edit: I apologize for not being able to answer the question clearly, I realized thanks to Longspeak. Trying to amend the fault, I would add to my first post:

You could make unarmed attack eligible for Sneak Attack but just for one try per turn, not the additional ones that can come after because martial arts and ki. If you miss your first attempt to make sneak damage, the enemy is aware of your devious moves and , even if you're not losing advantage, you can´t make it work for the moment (waiting until next round), and while on the heat of battle you have no seconds to lose and immediately take other course of action adapting yourself to the circumstances. Hopes this suits better for a proper subjective answer.

P.S.:Thank you Longspeak for being so polite in your correction. I notice and appreciate those details. Nowadays even more, since internet is so full with bitterness.

Have a nice day!

Answer 6

In an attempt to answer my own question, I'll state that I ruled yes on the basis that monk's may use Dexterity (and as a monk/rogue, obviously his Dex is higher than his Str) for his unarmed strike, as per Martial Arts, PHB page 79:

You can use Dexterity instead of Strength for your attack and damage rolls of your unarmed strikes...

and that's what the Finesse property does for weapons; it allows using Str or Dex, PHB, page 147:

Finesse. When making an attack with a finesse weapon, you use your choice of Strength or Dexterity modifier for the attack and damage rolls. You must use the same modifier for both rolls.

Given that rogue's sneak attack must use a ranged or finesse weapon, PHB, page 96:

The attack must use a finesse or a ranged weapon.

I ruled that unarmed strike, for a monk, essentially has the finesse property as per Martial Arts, and thus makes it eligible for sneak attack.

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I've just noticed (thanks to the Miniman and Miatog's answers) that my last quote says "a finesse or a ranged weapon", so given that unarmed strike is not a weapon, this wouldn't work RAW. I thought it important to update this answer with this detail since this answer hinges on that misinterpretation.

Answer 7

Everyone keeps saying monk unarmed strikes are not weapon attacks, but

Stunning Strike
Starting at 5th level, you can interfere with the flow of ki in an opponent's body. When you hit another creature with a melee weapon attack, you can spend 1 ki point to attempt a stunning strike. The target must succeed on a Constitution saving throw or be stunned until the end of your next turn.

Unless we are also saying that stunning strike only works with monk weapons, unarmed strikes from monks, martial arts specifically, must be considered melee weapon attacks. Whether or not they have the finesse property is a different debate, even though the definition of finesse is in the definition of martial arts for monks.

Would it really be so bad to let them have it? They overlap so much with rogue it probably would be a super strong build anyway.