A question about light weapons

[Spooferfish]

Does a weapon being signified as a light weapon just affect its use in the off-hand position? I.e. if a weapon is a light weapon, can I use a larger version of it as a one handed weapon instead?

For example, a dagger is a light weapon. A medium human can dual wield one in each hand pretty easily. On the other hand, count you use a large dagger as a regular one handed weapon instead of it being a light weapon?

I'm asking because I'm working on a Goliath dervish, and really want him to be able to use a Huge scimitar for the 2d6 and ridiculousness. In game, based on the way a light weapon is described, this makes sense - but I can't find anything in text that is definitive either way.

[JellyPooga]

I'm not sure of the intent of your query.

Are you asking if you can use a single Light Weapon without dual-wielding/off-hand? If so, yes, you can wield one Light Weapon single-handed.

Are you asking if a Huge sized weapon can be wielded as a Light Weapon by an, effectively, Large creature? If so, then I believe the answer is no. Although the Dervish lets you wield Scimitars as Light Weapons, the larger size means it would have to be wielded as a One-Handed weapon. So, yeah, I guess you could do it, but you wouldn't benefit from anything that gives a bonus to Light weapons.

[Spooferfish]

Sorry for the messy question, I'll try to reword it. I was focusing on the second answer you gave.

I was confused as to if a light weapon of a size larger used in the main hand can be considered a regular one handed weapon. What I hadn't accounted for, as you mentioned, was bonuses to light weapons - in particular, insightful strike. Considering this ends up being a +6 bonus if done well, it way trumps the 1d8 vs 2d6 I was looking at, and would affect both weapons.

Thank you!

[KillianHawkeye]

To answer your questions:

Designation as a light weapon affects Two-Weapon Fighting penalties, compatibility with Weapon Finesse, the ability to use said weapon while grappling, and an assortment of class features such as the Swashbuckler's insightful strike.

If you use an unusually large light weapon, it will become a one-handed weapon for you. An even larger one will require two hands to wield. Larger than that, and you cannot wield it at all. Be mindful of the -2 penalty for inappropriately sized weapons; the penalty stacks the more wrong-sized the weapon is.

A scimitar is normally a one-handed weapon. A goliath's powerful build trait allows them to wield weapons as though they were Large, so they could wield a large scimitar and it would still be one-handed. A huge scimitar would become two-handed, and the goliath would incur a -2 penalty from the weapon's size.

[CRtwenty]

Inappropriately Sized Weapons

A creature can’t make optimum use of a weapon that isn’t properly sized for it. A cumulative -2 penalty applies on attack rolls for each size category of difference between the size of its intended wielder and the size of its actual wielder. If the creature isn’t proficient with the weapon a -4 nonproficiency penalty also applies.

The measure of how much effort it takes to use a weapon (whether the weapon is designated as a light, one-handed, or two-handed weapon for a particular wielder) is altered by one step for each size category of difference between the wielder’s size and the size of the creature for which the weapon was designed. If a weapon’s designation would be changed to something other than light, one-handed, or two-handed by this alteration, the creature can’t wield the weapon at all.

From the SRD

[The Dark Fiddler]

Does a weapon being signified as a light weapon just affect its use in the off-hand position? I.e. if a weapon is a light weapon, can I use a larger version of it as a one handed weapon instead?

It also affects how your strength bonus to damage, how it interactswith power attack, and (I imagine) a few other feats and class features, but the interaction with two-weapon fighting is the most common one, I imagine.

You can use a larger version of a weapon, and for every size it increases by, it goes up a category, and it goes down a category for every size it decreases by (unwieldable > light > one-handed > two-handed > unwieldable). Thus, a normal human could use a huge dagger as a two-handed weapon, or a tiny greatsword as a light weapon.

It's noteworthy, however, that if you can actually wield the weapon in the size category it's designed for, then it stays the same category as what it's designated as for medium creatures. Killian and CRtwenty already went into that, though.