My ranger uses light crossbow. A few sessions back, he flavored his movement and attack as "I move there, and crouch before attacking." In character, previously he taught the others that it is better shooting while crouching, because it does not leave as much open spot. Impressed, I agree, and grants disadvantage on attacks against crouched target.

Disadvantage on all ranged attacks against crouching character, but different from prone, they can stand up and continued to move without movement penalty.

Crouching character also spend extra 1 foot movement per foot moved.

Now after a few sessions now he is consistently telling me that he crouches before he attacks and before he end his turn. After a few sessions, I think having all my readied attack against him got disadvantage, and attacks on my next turn, too, is ridiculous.

How should I modify this crouching rule so that it grants some sort of mechanical advantage, but not big enough so players can abuse it?

I don’t want to just switch to using the Prone rules, because Prone gives disadvantage when attacking, which crouching shouldn't.

Crouching is a no-brainer

And no-brainers are bad design --- you've created a new action that has a very negligible downside. No wonder your players are spamming it!

Think about it --- the only downside is moving slower, but the character can stand up for free, so that downside hardly ever comes into play if the player uses the rule to its fullest.

I would honestly recommend dropping the rule, since it overlaps with the already existing actions Dodge and Drop prone, and by what you describe it's not really adding anything but new rotes to your game. Crouching, bending, swaying and such to avoid ranged attacks is also something abstracted in the characters' AC.

But if you really want to fix it...

Disadvantage is too much for crouching. It's like dropping prone without any of the downsides. Also, the action needs to have a cost or condition to not be spammed in every possible situation. A mere "tweak" won't fix this, so if you really want to keep crouching in your game I propose this instead:

On your turn, as a bonus action, you can crouch. When crouching, any adjacent source of half-cover instead counts as three-quarters cover.

Making it cost one's bonus action introduces a reason not to do it, and restricting its use to places where cover is available makes sense in two ways. First, it reduces the potential for spamming this action. You can also explain that one needs to have a source of cover for the "reduced size" to significantly outweigh the defensive effect of having harder time moving.

The problem is that you're adding a new rule for this.

Basically, this doesn't need to be a separate mechanic. If it's something that every sensible person would do anyway - which mechanically is the case here given that you assign no cost to doing the action - assume it's already calculated into AC. Falling prone is what's there for the more drastic approach when you really need protection from ranged attacks without access to cover. Adding an extra rule for this would be like adding a rule that calculates AC differently if a player says their character will be alert to enemy actions during combat. This is simply redundant information.

My recommendation therefore would be to not attempt to tweak it, but rather drop it entirely and treat it as roleplaying fluff.

Disadvantage is too much for crouching

You could improve it by rewording it to be:

A creature may use half movement to enter a crouched position. While a creature is crouching they gain +2 AC against ranged attacks not stacking with cover or shields. they also have disadvantage on attack rolls until they use half movement speed to come out of crouch. A creature may not be both crouched and prone at the same time.

Crouching character also spend extra 1 foot movement per foot moved.

Making it a +2 to AC not stacking with shield or cover should balance it fairly well.

Note: I have not used this but it seems more reasonable and realistic than disadvantage.

Your rule is too broad

The change you proposed affects all characters, while the problem that sparked it is much more limited. I propose that you should not add a new option to all characters, but solve the problem of the ranger with using the rules for being Prone and adding this rule:

Being prone does not impose Disadvantage on your attacks with a crossbow. However, you have to spend a bonus action for a light crossbow or an Action for a heavy crossbow to reload it while Prone.

I'd like to answer just the question title, with a suggestion, based on the kinds of rule tweaking I often employ in D&D:

How should I modify this crouching rule so that it grants some sort of mechanical advantage, but not big enough so players can abuse it?

• Going into a crouch, and coming out of a crouch, costs 5 feet of movement. Movement whilst crouching costs +1 foot per foot of distance. This is strictly better than dropping prone and getting back up on their turn.




• A crouching character upgrades their cover by a single step against Ranged and Melee attacks (i.e. this does not improve dexterity saves against spells). If they upgrade from 3/4 to total cover, then they can no longer see their target either - e.g. think ducking or moving away when behind an arrow slit. This is usually a worse benefit than dropping prone, or could be equally achieved by moving around a corner etc.




• Melee attacks from adjacent positions against crouching characters gain Advantage, same as against prone characters. Note this is somewhat countered by the additional cover that the character has gained, but as an attacker, I'd usually still opt for -2 with Advantage.

I have not played those exact rules above, but have ruled similarly in ad-hoc situations where there was certain types of cover that players wanted to take better advantage of - e.g. gravestones in a graveyard. It worked fine in those circumstances, and gave a feeling of using suitable tactics in a ranged battle.

Crouching only helps when you have cover

Crouching in the open doesn't really do anything significant. Sure, it makes you a shorter target and might be a -1 penalty to ranged attacks more than 20 feet away at best (but when you consider that halflings and dwarfs don't get a bonus to ranged AC just because they're short, even this would be silly). Crouching really doesn't do much for you unless you have something to crouch behind which covers all or most of your body.

Crouching has drawbacks

A crouching player is less mobile and would have a harder time dodging attacks, especially in close quarters. So while it might give disadvantage against ranged attacks while in cover, it would also give any melee attackers advantage (or perhaps only +2 so that it is sort of a half prone state) against you. This gives you a tool to punish crouching spam with ambushes and high-mobility melee monsters.