Heatbased Dualblades

With dual blades, I wouldn't worry too much about ellement damage, try to get hold of dual swords with high attack and high sharpness (such as Bladed Edge, made from Shogun Ceanataur), also armour with the sword sharpener skill will be handy as weapons lose alot of attack when they lose sharpnes, hope this helps!

My weapon of choice is the lance. Ya it maybe slow, but the shield that comes with it makes up for it. You can block alot of strong attacks and you can also charge at your opponents with it. The lance also has a few good combos for it to.

I would recomend either sword and sheild (blocking with speed) or a longsword (speed with power)... But if you prefer dual swords and you want a fire element, then get the gradios and it's upgrades (bone scythe- bone scythe+- gradios).... It may not have sharpness at first, but if you can get at it, get the upgrades as soon as possible... Good luck

As far as fire element dual blades, your options aren't as open as I would like to tell you they are. Dual Blades in general tend to lack A LOT without a good amount of training with them. Personally I would go towards getting funky maraccas for their high damage and don't work about the sharp sword skill as dual blades come equipped with it. Speed sharpening is almost always a must unless you use the extreme sharps like insectors or bladed edge weapons which lack much in the powerhouse department making fights where you can't block take a long long time. For the mountain bosses(im assuming volcano?) I would go with something like the guild swords with the very high water element + sharpness for Grav if you must. For the most part gravios and bas are rock though and your better of with a water elemented bow. Some poison coatings for grav and sleep coatings for bas with some LBB+. If by mountain you mean the fort area, duals NEED dragon element IMO if you plan on taking either lao or gaoren down and is not really worth it compared to how much easier they can be killed with hammers. Good luck.