A double weapon counts the exact same as wielding a one-handed weapon and a light weapon when using both ends. There is no difference mechanically, ie you need the same feats to be effective and they have the exact same effects.
Some double weapons have slightly better damage than you'd have with a one-handed weapon and a light weapon like the orc double axe and dire flail which give you a d8 for both ends and I don't know that there's a light weapon that does a d8. Note: these weapons are usually exotic for most races.
If you have a double weapon someone only needs to disarm you once to make you weaponless. Sunder may work the same way here, I'm not sure though.
Dual wielding you could have more options, but typically people use the same weapon in both hands so they can take advantage of feats like weapon focus and improved critical.
You don't need any feats to make an extra attack with two weapons either, it just comes at a severe penalty without Two-Weapon Fighting.
Advantages of Two Weapons:
- Better crit range. As far as I know there are no 18-20 double weapons, and the only 19-20 one (two-bladed sword) is an Exotic weapon.
- The various swords, axes, daggers, etc are much more common than double weapons (besides the humble quarterstaff, with its poor 20 x2 crit). If you don't have access to people who will upgrade your weapon as you level up, and are relying on "finding" new weapons periodically, you may not always be able to find a bigger better Two-Bladed Sword.
- If you get disarmed once, you still have one weapon at least.
- Light weapons are usable with Weapon Finesse by default, while doing that with a double weapon requires yet more feats.
Advantages of Double Weapon:
- You can make two-handed attacks in situations where you can only make a single attack anyways (e.g. Standard Action attacks, and attacks of opportunity).
- You can take one hand off your weapon to retrieve an item, cast a spell with somatic components, or just to do stuff like operate a doorknob, without wasting an action to put one weapon away, or dropping one weapon.
Well, there are actually plenty of double weapons that do not need a feat. Besides the fact that dwarves adn half orcs (and gnomes, I guess) come with racial ones, the relatively new weighted spear is a simple weapon that is basically 'tape a light mace to a spear'.
Anyway, the main advantage and disadvantage are actually closely related- double weapons are better for strength builds.
Double weapons count as either a 2 handed weapon, or a one handed/light combo. Notice that you cannot get full use of weapon finesee on either of those (only some of the TWF attacks are with a 'light' weapon). So double weapons are bad for the traditional 'all dex' TWF builds.
But it is fantastic if you have a TWF build that focuses on strength. The ability to switch to two handing is rather nice for a strength build. You can go for the one big hit when you have to do a move action, or for AoOs.
So for the most part? Double weapons are probably a good choice if you are playing a ranger or slayer. It isn't impossible to pull off a good str TWF build using just stats.... but it is much easier when you can ignore the need for 17 dex.
Note that there is another style that gets the same 'two handing' benefits- this would be using a 1 handed weapon (such as a longsword) and a gauntlet style weapon. Gauntlets adn the cestus allows you to use that same hand for holding weapons, so you could just let go when you TWF. The advnatage of this is that you can grab rather good crit range (scimitar for 18-20/x2, cestus for 19-20/x3; compare that to the x3 seen on a lot of double weapons). But the disadvantage here is that you are using mixed weapons (so feats like weapon focus are not very good- which kind of hurts, since weapon focus covers half of your TWF penalty).
One (fairly minor, but so far unmentioned) example of double weapons, is only needing to have one weapon in your WBL budget. Magic weapons can get expensive. On the other hand, you are one weapon closer to being weaponless.
That would actually be a major advantage, but both ends of double weapons have to be enhanced separately, whether through Craft Magic Arms & Armor, or class features like Arcane Pool or Bane. Magic weapons are expensive, especially if you're paying retail.
Well drawing or sheathing the weapon is not an issue. He is proficient with the weapons and has a +1 BAB, so it's a free action anyway.
That's not how that works. If you have +1 BAB you can draw a weapon as part of a move action, but that's only if you move and to the best of my knowledge there isn't a similar rule for sheathing.
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Double weapons count as either a 2 handed weapon, or a one handed/light combo. Notice that you cannot get full use of weapon finesee on either of those (only some of the TWF attacks are with a 'light' weapon). So double weapons are bad for the traditional 'all dex' TWF builds.
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Weapon Finesse doesn't apply to either end of a double weapon. The "one-handed weapon and a light weapon" model only applies to TWF penalties.
Double Weapons: Dire flails, dwarven urgroshes, gnome hooked hammers, orc double axes, quarterstaves, and two-bladed swords are double weapons. A character can fight with both ends of a double weapon as if fighting with two weapons, but he incurs all the normal attack penalties associated with two-weapon combat, just as though the character were wielding a one-handed weapon and a light weapon.
There is no rule stating that one end counts as a light weapon for Weapon Finesse.
Well drawing or sheathing the weapon is not an issue. He is proficient with the weapons and has a +1 BAB, so it's a free action anyway.That's not how that works. If you have +1 BAB you can draw a weapon as part of a move action, but that's only if you move and to the best of my knowledge there isn't a similar rule for sheathing.
There is the Quick Stow feat from the Villain Codex.
You effortlessly stow items and sheathe weapons.
Prerequisites: Quick Draw, base attack bonus +1.
Benefit: You do not provoke an attack of opportunity when sheathing a weapon, and you can combine a move action to sheathe a weapon with a regular move action. (You can both stow and draw a weapon as part of the same move action in this way.) If you have the Two-Weapon Fighting feat, you can sheathe two light or one-handed weapons in the time it would normally take to sheathe one.
You can also quickly stow items in a backpack or other container that you are wearing or carrying. When you successfully use an action to pick up an item (including when you steal an item with a successful Sleight of Hand check or steal combat maneuver check), you can stow the item as part of the same action used to acquire it. You can try to hide this object by attempting a Sleight of Hand check with a –20 penalty, opposed by the Perception check results of all opponents.
Right I should have been more clear, I meant there isn't a general rule, and even thought about mentioning the feats but thought it was unnecessary.
The general rule is that you can draw as part of a move action if you have BAB+1, but if just having BAB+1 meant you could draw and sheathe then those feats would be pointless.
Right I should have been more clear, I meant there isn't a general rule, and even thought about mentioning the feats but thought it was unnecessary.
The general rule is that you can draw as part of a move action if you have BAB+1, but if just having BAB+1 meant you could draw and sheathe then those feats would be pointless.
You are correct that there is no general rule to accomplish this. I thought mentioning the feat might be a good idea in case being able to quickly sheath a weapon is an important part of ashuramarsh's build. The Villain Codex is new enough that a lot of people aren't yet familiar with it.