Well, as you said yourself, the Hippos were the victims. Not likely they would have caused this. Plus: the Hippos were already the group that was under suspicion the most. I figured the odds of a person going after the Hippos would be higher than a person going after the Dwarfs or Trolls. The Trolls were completely new to me (even if I mentioned them as an option during discussion - if I remember correctly when we were discussing the zombie), but I was afraid they had a rather large combat modifier. A Dwarf I can handle. I think.
That's a pretty good one. I didn't even consider that.