| Frogboy |
I don't have UC so I don't know what the special materials are but a good reason to take them is because once your weapon reaches +3, you'll be able to overcome DR Silver and DR Cold Iron. +4 will get you over DR Adamantine although you don't get the other special properties of adamantine. Eventually, a weapon with one of these new special properties will overcome all the normal DR types that usually require a more common special material and still add whatever properties that come with it.
| Kenjishinomouri |
why would you choose one of the new materials in ultimate combat for your weapons other than flavor?
They are more for if you wanna run a campaign setting that steel forging is rare or undiscovered. also those orcs you put up against your players maybe they have only been able to make their weapons out of stone. They are much more for flavor. I just ran a prehistoric game and would have killed for these materials.
Edit: I would have killed for platinum as an option. In one of my main campaign settings I have a npc who runs around in platinum full plate with a platinum longsword and platinum sheild.