In Darokin, the rapier is often paired with a weapon called the main-gauche, the rapier wielded in the primary hand and the main-gauche used in the off-hand to parry blows or make an occasional extra stab.
Darokinian Rapier & Main-Gauche Fighting
by David S LelandYou can fight with a rapier in your primary hand and a main-gauche in your off-hand. You can make one extra attack each round using the main-gauche or use it to parry incoming melee attacks.
Prerequisite: Int 11+, proficiency in rapier and main-gauche
Benefit: When attacking with a rapier and main-gauche, your penalties for fighting with two weapons are reduced by 2, resulting in a net two-weapon penalty of -2/-6 (see PHB Table 8-2: Two-Weapon Fighting Penalties, page 125). Further, you may exchange your extra attack with the main-gauche for a +2 parrying (dodge) bonus to AC against all melee attacks until your next action.
Normal: A main-gauche may be used with a rapier to gain an extra attack without this feat at greater attack penalties (i.e. -4/-8; see Attacking with Two Weapons, page 124, and Table 8-2: Two-Weapon Fighting Penalties, page 125, in the PHB). The main-gauche cannot be used to gain an AC bonus without the feat.
Special: The Ambidexterity feat reduces the attack penalty for the main-gauche by 4 (for a net two-weapon penalty of -2/-2), and allows the rapier and main-gauche to be used in either hand, but it has no effect on the AC bonus or rapier attack penalty when the main-gauche is used to parry. Note that the rapier suffers the -2 penalty to attacks for two-weapon fighting whether the main-gauche is used for an extra attack or for parrying. If the main-gauche is wielded but not used to attack nor parry in a given round, the rapier suffers no attack penalty. The parrying AC bonus does not apply to ranged attacks.
The above is based on my Darokinian Rapier and Main-Gauche Fighting feat that I posted to Eric Noah's 3e message board a while back. It is something of a hybrid of the Two-Weapon Fighting feat and Expertise feat, but not as powerful or versatile as those two purchased separately, and restricted to use with the rapier (on-hand) and main-gauche (off-hand) combo ONLY. While I refer to a main-gauche throughout, feel free to 1) consider the main-gauche a unique weapon with different stats from the dagger (see The Dagger, Main-Gauche, and Rapier below); 2) consider it a unique weapon needed to use this feat but in other respects statistically identical to a dagger, 3) consider it identical to a dagger for all purposes even though for flavour purposes some daggers (esp. many Darokinian ones) are main-gauches, or 4) just call the feat "Rapier and Dagger Fighting" and forget main-gauches altogether. If you decide that a main-gauche is a different weapon and that a regular dagger cannot be used for this feat, realise that this reduces the usefulness of the feat, and consider making proficiency in main-gauche free as a "cultural weapon" for Darokinians who already have proficiency in dagger, to compensate. Otherwise, characters will need two feats to attain these fighting benefits, and may be discouraged from picking this regional feat since they can get Two-Weapon Fighting and Expertise for the same cost of two feats, and those two feats are more versatile and powerful.
In anticipation of questions, here are some details on how and why I came about the various features of the feat. First of all, the intended use of the feat is for Darokinians, to allow colourful rapier and main-gauche fighting by even low-level Darokinian adventurers, without having to burn two feats for Two-Weapon Fighting and Expertise, and turning those characters into general weapon masters as a result of having those two feats. With the free feat available to 1st level human characters, even a Darokinian wizard could get access to this style of fighting at first level if he is willing to burn both of his two starting feats on this instead of magic-related ones (one feat for rapier, and one for the fighting style, if you don't require an extra feat for main-gauche).
Since Two-Weapon Fighting has no prerequisites, and Expertise, a more powerful and versatile feat, has just a 13+ INT prerequisite, I decided that this feat should only require 11+ INT and rapier and main-gauche proficiencies. While this feat takes features from those two feats, and is certainly a very versatile feat (helps attack or defence), I think it's balanced properly. Let's compare it to those two-feats. The Two-Weapon Fighting feat reduces your two-weapon penalties by the same amount as this feat (2 points), but for ALL pairs of weapons. Expertise allows you to take up to -5 to hit for a +5 to AC in a given round, on a point-for-point basis, using any weapon, and applying that AC bonus to any attack that is made against your AC. This feat effectively lets you make the same sort of trade since the rapier is at -2 to hit when you have the +2 AC parrying bonus, but you cannot choose a -1/+1 trade or a trade of 3, 4, or 5 points. You can only get this tradeoff when you use rapier and main-gauche together (and in the proper hands, unless you are ambidextrous). If someone manages to disarm either of your weapons during the round in which you enjoy the parrying bonus, you lose it. Furthermore, the AC bonus applies only to melee attacks, not ranged weapons or spells requiring an attack roll. Finally, because Two-Weapon Fighting and Expertise work with almost all weapons, all character classes can use those two feats without spending another feat on a weapon proficiency. The Rapier and Main-Gauche Fighting feat requires proficiency in rapier and main-gauche (or dagger), which is not free to all classes (e.g. wizard), so that some will need to spend a feat at least for rapier.
Here's a reminder of standard shield and fighting defensively rules in 3e, for comparison to what the feat's defensive capability gives you. Any character proficient with shields can use one to gain a +1 or +2 (depending on size) bonus to AC vs. all attacks requiring an attack roll, without a penalty to hit. Any and all characters can "fight defensively" in any round, taking a -4 penalty to hit for a +2 bonus to AC vs. all attacks. Used defensively, this feat effectively lets you use the rapier and main-gauche combination to take a penalty of -2 to attacks for a +2 bonus to AC vs. melee attacks.
One common criticism of the feat may be that if you just wanted to use the rapier and main-gauche all the time for your character anyway, the restriction to enjoying the benefits only with that combo is hardly a restriction at all. To answer that concern, here are some other reminders about the combo. First, this is a low damage combo: d6 and d4. Second, both attack types are piercing, which means no flexibility of attack type and low effectiveness against opponents like skeletons who take reduced damage from piercing attacks. Third, neither of these weapons can be used to make ranged attacks, unless you are substituting the regular dagger, which can be thrown, for the main-gauche. Even if you allow throwing the main-gauche/dagger, you lose your combo benefits without the main-gauche/dagger, and can't use the offensive or defensive capabilities of the feat in a round in which you throw the main-gauche/dagger, since hurling weapons is not part of the fighting style.
In summary, the Rapier and Main-Gauche Fighting feat boasts high flexibility and easy accessibility, at the price of more modest benefits, and tight restrictions to conditions of use (must be using the rapier and main-gauche). It is recommended especially for rogues, and if you like, could be also be integrated into a Darokin Merchant prestige class (which I'm working on). The Darokin Merchant prestige class could include rapier and main-gauche in its list of weapon proficiencies, and the membership could assure training in their use at a fair price. I would not recommend the feat as an free ability for that prestige class, but guaranteed access to training that leads to the feat if it is chosen would be a nice benefit.
THE DAGGER, MAIN-GAUCHE, AND RAPIER
If you want to have a new main-gauche weapon, here is a suggestion for how to treat it. The main-gauche is basically a dagger with a basketed hand guard or just a wider, sturdier hilt, for trapping blades. The difference in construction makes it 50% heavier and 50% more expensive than a regular dagger (3gp vs. 2 gp, 1.5 lbs vs. 1 lb). Also, the main-gauche is designed for parrying, not throwing, and cannot be thrown as a regular dagger (or you might allow it to be thrown with a -4 penalty to hit since it is poorly balanced for throwing). The rapier is like a thin longsword (but not as thin as a fencing epee) with a basket hilt.
You may recall from reading the Darokin GAZ that merchants and other wealthy people do not like to display their wealth with gaudy clothes and gems, but do like to show people how much money they have by spending a lot on very high quality items with functional value. Ostentatiousness is frowned upon, but items of masterful construction and artwork, and tasteful use of high value gems, etc. are fair game. For this reason, many wealthy Darokinians will own and wear rapiers and main-gauches worth many times the amounts listed below, whether or not they even know how to wield them in combat! Non-combatants may elect to have their weapons and scabbards filigreed with precious metals and encrusted with small, tastefully-placed gems, but not to the point where it is clear that the weapons would be non-functional or ruined as art objects if used in combat. Those more serious about using these weapons for defence will probably hold off on most or all of the embellishment and instead pay for masterwork weapons (non-magical +1 enhancement bonus to hit, +300gp to cost) and will rely on recognition of a master swordsmith's signature style, rather than precious gems and metals, to provide evidence of their wealth and status. For pictures of rapiers and main-gauches, check out http://www.by-the-sword.com/rapiers2.html
Dagger Cost 2gp, Dam 1d4, Crit 19-20/x2, RI 10', Wt 1 lb, Type P
Main-gauche Cost 3gp, Dam 1d4, Crit 19-20/x2, RI -, Wt 1.5 lb, Type P
Rapier Cost 20gp, Dam 1d6, Crit 18-20/x2, RI -, Wt 3 lb, Type P