You may already know this, but our store is different from other stores in the region. We combine high-grade weapons to create Dualswords.
We are able to combine almost every type of sword. If we can't...well, then you should go to the capital or seek out the Blacksmith of Mammon. You never know... There might be a capable blacksmith hiding where you least expect him.
However, crafting Dualswords isn't only about skill and technology. The Merchant Guild controls how many Dualswords can be made in order to prevent a glut.
The number each territory is allowed to manufacture isn't large, so it's difficult to acquire a Dualsword Craft Stamp.
If you do happen to acquire a stamp, bring it to me with the swords you want combined. I promise I will make you a magnificent weapon!
The two swords to be combined into a Dualsword must be either Superior weapons, Common weapons or Masterwork weapons.
Superior weapons can be combined with other Superior weapons, Common weapons can be combined with other Common weapons, and Masterwork weapons can be combined with other Masterwork weapons. Even a Masterwork type must be above B-Grade.
Oh, another thing. If you invest some kind of a skill in a weapon, you can't combine it with another.
Remember as well that an Enchanted weapon loses its effect once it is combined with another.
Now, select a weapon.
Look at the list.