I'd have to go with the wolffish also. I tried to look for the video on you tube but cant find it now. Its of a recently caught Wolffish in a tank and its trying to attack the guys looking into the tank through the glass. Makes you wonder how these things get along long enough to even breed.
most agro ive owned would be red devil & mangrove jack,but when you talk bout nuts fish i have no doubt a giant snakehead and a piranha would have them both for dinner.
needless to say, there is a wrong and right answer.
cr8on is close tho. there is NO fish on this planet as mean as a Giant Snakehead. Reasons being :
1. Have you seen one lately?
2. They wipe out entire ecosystems, not just a few species. If a GS is 30 inches, he will eat EVERYTHING < 30 inches! and then it will still bite everything larger
3. THEY ATTACK HUMANS! like a Sci Fi movie!!!!
wrong answers are everything not relating to snakeheads