Monks catching and/or deflecting shatter-on-impact alchemical projectiles

[TheFirstStraw]

I couldn't think of a more concise way to phrase it at the moment, but essentially I will be running an encounter in an alchemy lab, and the party is going to have a bunch of vials of random whatsits thrown at them by enemy combatants:
alchemist's fire
flasks of oil
tanglefoot bags (converted to 5e)
philters of love
maybe even a vial of sovereign glue if I'm feeling cruel

However, one of the PCs is a monk, and I would love to give her some utility in deflecting or even catching some of these "missiles," but that ability specifically reduces damage from the weapon's impact and doesn't account for delicately handling something.

Starting at 3rd level, you can use your reaction to deflect or catch the missile when you are hit by a ranged weapon attack. When you do so, the damage you take from the attack is reduced by 1d10 + your Dexterity modifier + your monk level.

If you reduce the damage to 0, you can catch the missile if it is small enough for you to hold in one hand and you have at least one hand free. If you catch a missile in this way, you can spend 1 ki point to make a ranged attack with the weapon or piece of ammunition you just caught, as part of the same reaction. You make this attack with proficiency, regardless of your weapon proficiencies, and the missile counts as a monk weapon for the attack, which has a normal range of 20 feet and a long range of 60 feet.

Has anyone seen precedent for a ruling on that, homebrew or otherwise? How would you run this?

(P.S. as it costs her reaction, she can only do it once per round and there will be plenty more than that incoming, so I think the solution here will make her look cool without totally nerfing the encounter.)

[Lombra]

Just let her catch it, it makes sense that if she can catch an arrow she can also catch a vial of something without breaking it.

[BobZan]

If it targets the Monk, I'd say yes. If it targets an area, I'd say no.

It's tricky because Deflect only triggers after damage has been aplied, in that sense the vial is already broken.

Maybe you can make a resisted check attack vs dex save to determine if he can catch it before it breaks.

[Pleh]

Well, you could run it as written. Roll damage for the attack as normal and if the monk reduces the damage to 0, the vial didn't shatter.

If it doesn't shatter, it doesn't splash adjacent squares.

NPCs who don't want to risk their vial being caught can target the square next to the monk (giving the monk advantage to dex save on avoiding AoE damage)

[MightyDuck]

Alchemist fire counts as an improvised weapon and requires you to make a ranged weapon attack which means that a monk can definitely catch it and throw it back, since the weapon doesn't do direct damage and the damage it does do is only a 1d4 then it would just be an auto success, I'm not so sure about the other items though but I'd reckon it would work, if not I'd probably let it anyway, maybe have the monk make an dexterity check to try and catch it.

[LordEntrails]

For those items that don't do HP damage, I would have the monk make a Dex Save vs a DC 14 or so to catch it. If they fail by more than 5 then they break it with their hand and suffer critical damage or disadvantage on the save (as appropriate).

As mentioned, if the floor next to the monk is targeted (to prevent the monk from catching it) then the monk gets advantage on their save or the attack roll is at disadvantage.

[Galadhrim]

For those items that don't do HP damage, I would have the monk make a Dex Save vs a DC 14 or so to catch it. If they fail by more than 5 then they break it with their hand and suffer critical damage or disadvantage on the save (as appropriate).

As mentioned, if the floor next to the monk is targeted (to prevent the monk from catching it) then the monk gets advantage on their save or the attack roll is at disadvantage.

The original ability does not have any type of consequences built in, it is simply a boon to the monk. I would avoid adding any punishment as described here (critical damage or disadvantage to a save). In general the ability just works, so if you are going to add a save for careful handling, I would make it a relatively easy save. If the monk fails it, the thrown object should function as it was intended to function. This is an encounter where the monk SHOULD shine, and adding too high a save could actually turn their ability into something that harms them. That is not the intent of the ability.

[TheFirstStraw]

I agree with much of what's being said here.

I think setting a low DC Dex save is appropriate for catching it, and the cost of a ki point to redirect it is enough of a tax that I wouldn't increase it.

It makes sense for the enemies to wise up and target the floor adjacent, although I might allow her to ready an action to move and catch the first vial thrown within 10ft of her. In theory this should be more difficult, but if it is costing a turn, then I am okay with keeping the same DC.

It just sounds more badass to jump in front and reject that mess like a basketball. "Not in my house, wizard!"

Probably that is 2 reactions in RAW, but "rule of cool."

[KorvinStarmast]

Alchemist fire counts as an improvised weapon and requires you to make a ranged weapon attack which means that a monk can definitely catch it and throw it back, since the weapon doesn't do direct damage and the damage it does do is only a 1d4 then it would just be an auto success, I'm not so sure about the other items though but I'd reckon it would work, if not I'd probably let it anyway, maybe have the monk make an dexterity check to try and catch it. As the skill is written, the auto success seems a mortal lock. Let the monk shine, thinks I. She isn't the only one stuff will be thrown at. If she tries to catch something thrown at someone else ... yeah, ability check.

[Chronos]

It makes perfect sense thematically for the monk to be able to catch thrown vials; the question is just how the mechanics for it work. The closest I can figure to making the rules as written work is to calculate the damage that the vial would do if it broke, subtract the monk's deflect arrows amount, and if that brings it to zero or less, then say that it didn't break after all. But that ends up working really weirdly: It means that (for instance), if one vial contains a weak, dilute acid that only does 1 point of damage, but another vial contains a magically super-strong acid that does 3d6, that it's harder to stop the second vial from breaking, even though the containers themselves are the same.

I think the best way to run it is the way that I think that MightyDuck suggests: If someone were throwing empty glass vials at the monk, or vials of something harmless like plain water, those would only do the 1d4 damage of an improvised weapon, but it should be the same difficulty to catch a vial of water unbroken as for a vial of acid. So roll 1d4 damage for the vial, compare that to the monk's roll, and it only breaks (doing whatever the contents do) if the 1d4 roll is greater than the monk's roll.

[Ganymede]

The highlight of this thread is the suggestion of using Philters of Love as missile weapons.

On the topic, I'd definitely allow directly targeted grenade-like weapons to be caught and thrown back.

[Mith]

An extension to this, would it be too much to have the monk catch up to 1 missile per hand (if they end up with an extra limb some how, they can use that)? I just think that if two people shoot at z monk with this ability, then the monk should be able to catch both.

[TheAxeman]

I would say maybe, maybe if they use deflect missile make them do a dex check to see if they can catch the vial without it breaking.

[CorporateSlave]

The original ability does not have any type of consequences built in, it is simply a boon to the monk. I would avoid adding any punishment as described here (critical damage or disadvantage to a save). In general the ability just works, so if you are going to add a save for careful handling, I would make it a relatively easy save. If the monk fails it, the thrown object should function as it was intended to function. This is an encounter where the monk SHOULD shine, and adding too high a save could actually turn their ability into something that harms them. That is not the intent of the ability.

This!

Geez you guys, adding all kinds of Dex saves and damage risk to this?! It already eats the monk's reaction for the turn, and of course a Ki point if they want to throw it back. The ability is there to let a monk avoid damage from a single ranged attack. There's already a dice roll to see how much damage can be deflected, no need to add another! Frankly, if you're going to get crazy with Dex saves and ability checks, then I think you should apply that to any PC (or NPC) who is directly targeted with a throw, and let everyone have a shot at catching it! (not that I think that's actually a good idea)

I do like the suggestion to allow the monk to ready their action to try and catch a vial thrown within 10' (or whatever distance you want to allow). But given the deflect missile ability, I would tie NO additional dice rolling to this, other than the usual damage reduction. Its now costing both action and reaction. That's a plenty high price for what amounts to a minimal amount of damage mitigation but with a cool factor!

Granted it's just my opinion, but fun is supposed to be the main goal of the game, and nothing digs at my personal fun more than a DM feeling like they need to add some sort of die roll to a novel use of an ability that really should just work; because "its a game about rolling d20 for everything." Of course, if that were really true, we wouldn't have Passive Perception*, or AC for that matter. (now if Deflect Missiles RAW did have a risk of critical failure, such as a Dex save to catch the missile IF damage was reduced to 0 or end up taking the damage anyway, then I could see adding risk to catching a vial or flask. But that would make it idiotic to EVER try to catch the missile).

*BTW, if anyone is curious, and I know you're not...this is one of the big ones for me. Things that obviously should key to passive perception and the DM has people make perception checks anyway. Inevitably the "keen eyed" rogue with 22 passive perception manages to roll a 2, and their 14 check total misses the 16 stealth check for the ambush up ahead. And at the same time, they DM has just let the players know something is up that their PC's haven't noticed. #boo! (I get it that a check can be more appropriate during combat or when looking for something/someone in particular.)

Last thing to get back to the OP, I do like rolling out the damage for the attack, then having the monk roll to reduce, with a catch possible if reduced to 0, meaning the flask didn't break. If this doesn't "make sense" to someone, think of it this way - is it really that different than with a arrow? You're still rolling for potential damage that would have happened IF the monk hadn't deflected/caught the arrow. It is sort of "looking into the hypothetical future" in either case.