One who purposely and deliberately (that purpose usually being self-amusement) starts an argument in a manner which attacks others on a forum without in any way listening to the arguments proposed by his or her peers. He will spark of such an argument via the use of ad hominem attacks (i.e. 'you're nothing but a fanboy' is a popular phrase) with no substance or relevence to back them up as well as straw man arguments, which he uses to simply avoid addressing the essence of the issue.
A visceris is a person who is consistent his inconsistencies. He will very occasionally make claims attesting to some thing and at any given moment, refute everything that he had claimed with justifications and excuses after he is proven wrong.
Robert is a real visceris when it comes to religion. He has been through 9 religions in the past year and each time he finds a new one he has nothing but derogatory remarks to say about every other religion until he finds a new religion and repeats the process.