I'd have to say Fahaka puffers, not only because I currently have one.. I've never had a snakehead but they seem vicious on Youtube videos. My old fahaka grew up to 12" , but max size is supposedly 17" or so. When I had my old fahaka & I was trying to experiement by adding tankmates hoping that they can co-exist... But nothing was able to live with him. Tried a 10" FLowerhorn that was mean as well, but the fahaka bit his lower jaw off & ended his life. Im not sure how a Fahaka would fend off w/ a SH, but that would be the ultimate match imo.