User blog comment:AltertheSilverBird/Total Drama: Danganronpa./@comment-2212492-20151226093520

By process of elimination, it can be supposed that neither Alejandro nor Heather did the murder as they promised to do it when two people were killed. The remaining suspects were Amy, Rodney and Dave. Seeing as Dave would probably kill Sky instead, I'm going to say Amy talked Rodney into killing Staci because she was the one who had the gun.

So I vote Rodney.