It is considered bad sportsmanship to cuss or try to intimidate your opponents.
Sportsmanship typically is regarded as a component of morality in sport, comprised of three related and perhaps overlapping concepts: fair play, sportsmanship, and character (Shields & Bredemeier, 1995). Fair play refers to all participants having an equitable chance to pursue victory (Weinberg & Gould, 1999) and acting toward others in an honest, straightforward, and a firm and dignified manner even when others do not play fairly. It includes respect for others including team members, opponents, and officials (Canadian Commission for Fair Play, 1990).
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When you are playing for the purpose of winning, you are not trying to make the game as fair as possible, you are trying to win. This means trying to always tilt the scales in your favor (e.g., ganging up on opponents, taking advantage of failed base moves or other screw-ups, spawn camping). Is going into the alien base when aliens are at stage 1 with a battlesuit and lucifer cannon fair? No, but it's a good way to win if it can be pulled off. (I'm not talking about artificially inflating the human stage.)
Character refers to dispositions, values and habits that determine the way that person normally responds to desires, fears, challenges, opportunities, failures and successes and is typically seen in polite behaviors toward others such as helping an opponent up or shaking hands after a match. An individual is believed to have a “good character” when those dispositions and habits reflect core ethical values.
Nobody does this in an online game. When you get creamed, you're usually frustrated and going to take it out on your opponent and when you cream your opponent, you're going to be a bit cocky. Ever notice that it's usually the winners saying "gg" at the end of a game?
Clan "war" alludes to warfare which is very dirty and unsportsmanlike. It is very uncommon to see a friendlier version like "clan contest". You will sometimes see "clan match", but that seems less formal to me. Even so, the purpose is not to have fun, but to be victorious.
n general, sportsmanship refers to virtues such as fairness, self-control, courage and persistence (Shields & Bredemeier, 1995) and has been associated with interpersonal concepts of treating others and being treated fairly, maintaining self-control in dealing with others, and respect for both authority and opponents. Five facets of sportsmanship have been identified: (a) full commitment to participation (e.g., showing up, working hard during all practices and games, acknowledging one’s mistakes and trying to improve); (b) respect and concern for rules and officials; (c) respect and concern for social conventions (e.g., shaking hands, recognizing the good performance of an opponent); (d) respect and concern for the opponent (e.g., lending one’s equipment to the opponent, agreeing to play even if the opponent is late, not taking advantage of injured opponents); and (e) avoiding poor attitudes toward participation (e.g., not adopting a win-at-all-costs approach, not showing temper after a mistake, and not competing solely for individual prizes; Vallerand, Deshaies, Cuerrier, Briere, & Pelletier, 1996; Vallerand, Briere, Blanchard, & Provencher, 1997).
Going to give your opponent a weapon because his teeth are a little dull? No, you're going to take advantage of it. You don't respect your opponent; you want to kill that bastard. After you win, you can worry about being friendly, but during the match? Hell no. (If I were in a clan war and my opponent was being really nice and courteous, I would think s/he was up to something, and I would probably be right.)
