Well, will be kind of fun to "guess" when the time comes. They are already lining up potential choices for perhaps "the killer", if indeed it is Deimos who is done in.
Some years ago, I really loved the one where it was Stefano who was murdered. It was a dark and stormy night, claps of thunder, pouring rain, Stefano sitting in his small study, in front of the fire, listening to opera, his high back chair facing the fireplace, back to the door. And we see various Salemites at various times sneaking into the house one way or another, intent on doing him in. And finally the black sleeved, black gloved hand is firing the gun at the chair from the doorway. Alas, Stefano has gone to meet his maker. (Only there was a change of writers, change of mind, and it turned out the victim was a lookalike, planted by some ex-boyfriend of Kate's, Ian, who felt he was actually a DiMera and wanted the role of head of the clan.) LOL