So, I'm batting around the idea of making a new civ (as I'm sure every DF player does before long), which has hit a stumbling block that may or may not be surmountable. I'd really appreciate all help/input on it, even if just to say it can't be done. My specific idea is a civ that, though industrially backwards and low-tech in almost all spheres, has honed an understanding of genetics to the point of being able to utilize limited biotechnology. The specific spot where this hits a problem is in material. The idea I've been batting around is creating one or two new materials, probably "Blubber" (composed of a large quantity of smelted fat) and "Muscle" (smelted chunks and meat), that can be used for weapons/armor/furniture/whatever. Now, getting them to be unable to use advanced metals should probably be as simple as removing their ability to have stone prefs, it looks like. But is there any way to specify that their non-clothing equipment should primarily be made from these materials? Also, is it at all possible to restrict the ability to create items from these materials to their civ? If they're used purely as NPCs and I can make them use blubber/muscle items then that's probably one easy way, but ideally I'd love to be able to include appropriate reactions so one can switch over to them as a fortress race with a minimum of fuss. Thanks for any and all help!