Taiga: can you tell me why you put proof in parentheses? Do you have counter-proof? Don't you trust Yuna? Because you seem to have no such reservations with rana's claim that no magic was used, or Berg's that the Hippos are not behind it. For all we know either could be lying to save their own group.
Obviously I have no counterproof as I chose option 9. The proof in parentheses was not mistrust, but I assumed it was only overheard as Yuna followed the dwarf. However, the parentheses can go now, because you have more or less confirmed the story. From both stories we can conclude that the Dwarven Smith is responsible for the collapsing bridge at least.
As for my choice of option 9, it's more or less the same as prazi and FT. I liked it that I could choose a stat and besides I figured we were going after a humanoid Hippo. But this is discworld eh :S. The plot that the hippo's knew more about the collapse seemed reasonable to me, as no one died and there were only scratches and bruises.