<div class="quote"><i>Neo Bahamut wrote:
I can't look into it much right now, but I think igneous rock is actually pretty weak. At the very least, I know that pumice & obsidian are.</i></div>
<p>Those aren't really true igneous rocks - Pumice is made of volcanic dust forming something more like a poorly cement sedimentary rock, breaking up if improperly handled and obsidian isn't even techniquely a rock (made of glass not crystals). Rhyolite and Basalt is what would usually form when lavabenders cool their lava, and those can serve as effective building materials. I think if a Lava bending tribe existed, they'ld live on or near a very active volcano, using their power to protect their homes and fields. Probably suffered losses during the early days hundred years that nearly destoryed the culture, as fire benders invaded their territory to claim it's sacred volcano for themselves.
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</p><p>I think there is combustionbending tribe, who are nomads traveling the Fire Nation, afraid of persecution because their powers. Both Combustion man and P'Li are from this culture, or are descended from it.
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