Backstabbing is when you join a team game, and attack your teammates. Usually backstabbers have a plan to wait and build up, then attack the stronger players at once, leaving the weak players to die. Backstabbing is a more common thing.

Any frequent Starcraft player is familiar with the term "BS," known either as bullshit or backstab. A popular phrase in melee games is "no bsing," which insists the players and host don't want trouble from backstabbers, but rarely works and only draws more attention.

Ну и так далее
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