They are not trying to say that about Oscars. They are just saying for the most part the fish on most of these list are 95 percent of the time aggressive. I am sure that your Oscar is aggressive but most of them are not. There are individual fish like your Oscar that is not the norm and does turn out to be quite aggressive. They are just asking for the top ten fish that are almost all aggressive. Most Oscars are not aggressive you just happen to come across one that is and that does happen.