A rapier and shield was not really an historical combination, whereas Rapier and Buckler was. In addition, people seem to be worried about the advantages of a dex fighter over a str fighter, so making rapier and shield less likely may help with this.
Proposed Changes:
1. If Rapier used with a Shield, then any attacks with the rapier suffer from disadvantage.
2. Introduce the Buckler. A Buckler gives +1 AC and does not count as a shield when used with a rapier.
3. The Dualist Fighting Style does not work with a rapier if the other hand is holding a shield, but does if the other hand is holding a buckler.
4. The Defence Fighting Style can be used if you are using a buckler, even if you are not wearing armour.
On another thread, i talked about how rapier and dagger were an historical combination, but how in D&D this fighting style won't really be used. As the dagger only does a D4 I thought it would be allright if it has the ability to be used in the off hand if the primary hand was using a finesse weapon that was not light i.e. a rapier. Someone pointed out that this might be too big of an advantage, as the dagger could be thrown. So, my solution is to introduce the Main Gauche - a dagger that cannot be thrown (because of the hand guard it has) but can be used in conjuction with a non-light finesse weapon (rapier). So:
5. Introduce the Main Gauche. A Main Gauche does a D4, is considered light, cannot be thrown, but can be used in the off-hand if the prime hand is using a non-light finesse weapon.
Thoughts?
Iorwerth wrote:
yes, was meant to be a finesse weapon 
I don't understand what you're trying to do here.
Currently "rapier and buckler" (as rapier and shield) is a perfectly viable build, and is only overpowered if you're the sort of person who obsesses about minute differences between nearly-equivalent characters based on extremely hypothetical issues like whether more spells require one save over another.
The limitations to rapier-and-dagger in D&D are simply that a dagger is an inferior weapon to the shortsword. There is no way around this.
Thoughts_My_Aim wrote:
Have you considered just using Katanas?
Your proposals are clumsily worded. Currently your "main gauche" does nothing, since while it "can be used in the off hand" if the main hand weapon is a rapier, that does not itself trigger the two-weapon fighting rules. I'm also not wild about the idea of a weapon that is somehow magically able to be used in a way that other weapons are not. I'd also-also point out that the point of "rapier and dagger" was not, as far as I can tell, that you would attack with the rapier and dagger simultaneously.
A better option would be a feat along the lines of Tavern Brawler that let you make an offhand Dagger attack as a bonus action on the same turn that you attacked with a Rapier. It would, unfortunately, be strictly less good than Two Weapon Master.
Thoughts_My_Aim wrote:
Iorwerth wrote:
I would like to see Rapier and Buckler with a shield bash. Just not sure how to make it mechanically feasible as I like the current balance of fighting styles.
there is no reason to houserule this. if you don't like it then just don't use it. I have a duelist fighter who owns a shield but rarely uses it because i choose to have my second hand open. that is all that you need t do. use a smaller shield and enjoy yur buckler or use no shield at all. rather tan support your own play you are trying to ruin others enjoyment. there is no historic rule tat rapiers cant be used with a shield. The rapier itself is actually a ver broad category of weapon from sender blades up to and including weapons indistinguishable from the longsword. Rapier is simply the italian term for sword. This game has separaged rapier and longsword for a rock paper scissors P S B weapon design which arbitrarily assigned piercing and slashig to them separately where in reality bot weapons were used for both functions. A man going to war wit a rapier would not turn down a shield if offered one. tey simply did not carry a shield in everyday business within a city so we have te impression that rapiers and shields do not mix. when your life is on the line you will use every advantage you can gather regardless of whether it looks cool or not.
Iorwerth wrote:
The buckler was more commen in Roman gladiator games. The reason you used a dagger was you would look funny walking around the streets of Italy carrying a shield, rapiers and daggers became briefly popular. Dueling was made illegal once the death rate in Italy hit around 300 men per year in the 16th century IIRC.
Buckler=shield works fine for D&D. No new rules needed.
Main Gauche could be light finesse 1d4 piercing OR +1 AC as a bonus action. Now, this would mean TWF feat is required to use with rapier but that reflects the skill of the user (which historically only the best faught florentine or nito style).
strider13x wrote:
Zardnaar wrote:
MechaPilot wrote:
Zardnaar wrote:
MechaPilot wrote:
I like feats for simulating difficult fighting styles.
spelley wrote:
Anyone can fight with a dagger and rapier, anyone can fight with a rapier and buckler. I would give a bonus to people who specialize in that style of combat.
Iorwerth-
Yes, I was thinking the Main Gauche would grant the +1 AC as a bonus action when used off-handed and not used to attack (it would replace the attack from TWF). Now, all of the other TWF restrictions apply (both weapons must be light) so to use Rapier would require the Feat (or a new fighting style for Fighters/Paladins/Rangers).
strider13x wrote:
Iorwerth wrote:
Thoughts_My_Aim wrote:
How’s this:
Rapier: 1d6 Piercing. Light. Finessable. Versatile (1d8).
Not that you actually need two hands to swing a rapier, but having a free offhand allows you to wield it properly, and thus the damage boost.
Bucker: +1 AC
When a bucker is used along with a versatile weapon, you may use the higher damage die of the versatile weapon.
Dagger: 1d4 Piercing damage. Light. Finessable. Thrown.
When used in the offhand along with a versatile weapon, you may use the higher damage die of the versatile weapon.
With these rules, rapier/bucker and rapier/dagger are strong options out of the gate, with no feat or special training. A finesse dual wielder would even be incentivized to use rapier/dagger after he has the feat (instead of the silly two rapiers).
As a side effect, it gives some beef to the versatile quality in all weapons. You can go halvsies between great weapon fighting and sword and shield and have a battleaxe/buckler build. Or, once you have the dual wielder feat, longsword/dagger looks pretty good.
Or, you can just think of a main gauche as a type of rapier, and a buckler as a type of shield, and just assume they are the type being used when one goes rapier/rapier or rapier/shield.
While I see that Rapier + Buckler or Dagger has a more historical touch to it, I just can't see why a larger shield would get in the way of fighting with a rapier and not other swords. Althought historically the buckler was coupled with it more often as a fighting style, there is nothing inherently different in the rapier as a sword in itself that would make it be more clumsy to use with a shield than other swords.
If you really want to make that flavour come out add some salt & pepper to it instead of applying ketchup all over the dish. Give no hindrances to standard use of shields or rapiers, but make a "Swashbuckling" feat or something like that and give special bonuses to people coupling Rapier and Buckler or Dagger.
Rastapopoulos wrote:
The rapier is currently filling the rank of 1d8 finesse piercing weapon. It's easy enough to reflavor as something like a spatha or an early viking sword if you don't like the idea of rapiers with shields. While not particularly popular nowadays, rapier and rotella was a thing at one point.
Shields started to fall into disuse with advancements in plate armor. Plate offered so much protection when set against the weapons of its time that many warriors started to let go of the shield and sometimes would use two handed weapons.
The buckler is certainly more portable than a war shield, and in a post-renascence setting it would indeed be weird to have people walking around with shields. Not much beacuse of weapon melee weapon choice, really, but because the more firearms became widespread and common in warfare the less armor and shield had any use. A bullet could generally just ignore both after a certain period in the development of firearms.
However, since we're talking about fantasy worlds where maybe the combination of Rapier and large shield could possibly be a thing... I was just mentioning that I don't see anything impractical in the Rapier as a sword in itself that should impose a penalty when paired with a shield, when compared to other weapons. Just because it feels strange when we think of them in the context of our own history and the moment those items were most in use... doesn't mean in theory it couldn't work... 
This whole thread is built on the faulty premise that Rapier and Shield was historically innacurate and that Rapier and Buckler was what it should have been.
1. Read Capo Ferro. He teaches Rapier & Cloak as well as Rapier & Rotello a roughly 2' diameter shield. Shield. Not Buckler. Bucklers are mostly the size of a dinner plate and were primarly used for punching and actively deflecting enemy blades. 16th Century combat was rife with this combo.
2. Daggers were used for stabbing the **** out of your opponent close in after your rapier took his out of line and you closed corp a corp (body to body) to knife the guy in the guts.
3. House rule all you want. The game plays perfectly the way it is. Splitting hairs further is your perogative, but I'd leave it alone if it were me.
I would totally allow rapier/dagger as a two weapon fighting style, since average damage is the same. I might make it a requirement to have a 'proficiency' in this style, gained through a background or campaign event.
I think a 'maing guache' weapon would also be cool. Usuable with both the rapier, and any light weapon, it would allow a character to use their bonus action to attack (as a dagger), or deflect (+1 AC until the start of your next turn). But it could not be thrown. It would be a martial weapon.
This only feels correct in an renaisance/early modern setting. If you want a more medieval, knightly feel, I would not use rapier/dagger rule, or the main gauche rule.
Not really getting why it's necessary to make a slightly different thing to replace the shield for flavor reasons. In game terms, a shield is a defending thingy that occupies one hand and isn't used to kill stuff. +2 AC. You can have it look like anything you want. Say it's a buckler and part of the AC bonus comes from increased maneuverability. Say it's a dagger used defensively, rather than using default two-weapon rules to flurry attacks with both weapons constantly. Or hell, say it's nothing, just your empty hand or a gauntlet improving your defense by dodging expertly. It's all just numbers, what they actually mean is up to you. If that breaks your immersion somehow to see it on your sheet, record it as "Main Gauche - +2 AC." A DM shouldn't have much problem allowing you to treat that shield as a dagger instead on any given round.
Weapons in 5e are simplified like this for a reason. You generally don't have a bunch of nearly-identical weapons with different perks, exotic weapons, etc. (except battleaxe/longsword and such). Instead, you have a weapon archetype to fit each point on the spectrum and keep balance. If you want a kopesh, harpoon, composite bow, or ice pick, you grab the most appropriate set of numbers and go. In this case it's just the shield="buckler" as a flavor option. If you want additional refinement of the style, invent a homebrew Fighting Style that isn't Dueling, or make a feat that improves the style after a few levels. Keep in mind that Lv1 is practically a commoner who picked up weapons, Lv3 is a competent fighter, and Lv4 is a perfectly it acceptable point to "perfect" some specialized fighting style beyond what a grunt would know.
I think of the D&D rapier like the Green Destiny blade from Crouching Tiger, Hidden Dragon.
Historically, rapiers were used with shields. This is a rotella and rapier illustration. In fact, some sources say that historically, bucklers were used with small swords, and rotella were used with longer rapiers. 
Here's a idea: houserule the two-weapon fighting style for fighters and rangers:
Two-Weapon Fighting
Choose one:
- You can engage in two-weapon fighting when the weapon in your main hand is not light. In addition, when you engage in two-weapon fighting, you add half your ability modifier to the damage of the second attack.
- When you engage in two-weapon fighting, you can add your ability modifier to the damage of the second attack.