Blair nodded. "Yes. I can't think of how one could do so without leaving an obvious mark on the body. Electrocution would leave scorch marks and more visible damage - not to mention bruising and such from the victim flailing - and poison generally has noticeable physical effects, and there would have to be a visible injection point." Blair fell silent for a moment. "I suppose something affecting the brain, possibly though the Duel Gazer could be feasible, but I don't have knowledge of any way to do so without leaving any marks on the body." Blair turned off her bike and stuffed the key into a pocket, then got off and began to pace. "I suppose you could do something with a very forceful kind of electromagnetic wave - you know, the kind in the movies that shorts out electronics? They do that in real life too. If you found the right way to apply them, I suppose it might be possible to kill someone by causing a sufficient disruption in the brain. This is all speculation, though, I really have no idea if that's biologically possible without just blowing a hole in someone."