23rd Oct: It's time for the second TV Tropes Halloween Avatar Contest, theme: cute monsters! Details and voting here.
Friendly fire, isn't.Combat or other dangerous elements in a setting or plot conflict increase the drama by exponentially increasing the danger to the characters. But sometimes that danger comes from an unexpected angle. You look up to see who is on the other end of the knife you've just been stabbed with... and it's your best friend!?! This sort of thing can occur by accident, by treachery, or, perhaps most tragically, because they had to. In Real Life, friendly fire usually occurs as a case of mistaken identity: innocent civilians, allies, or neutral forces, are mistaken for enemy forces and fired upon, or else the attacker simply didn't know the friendly unit was in the line of fire. While it might be hard enough to imagine the horror of killing someone you like accidently, in fiction, to play the drama up even more, the attacker often is all too aware of what they are doing. Note: Please place non - trope examples in the subtropes listed rather than listing them here. There are many forms of Friendly Fire, from nastiest to least nasty:
— Murphy's Law of Combat Operations
Category A: Deliberately, out of a callous disregard for life (note: doing any of these invariably marks you as a villain or Anti-Hero):
Category B: Deliberately, out of treachery:
Category C: Deliberately, due to being faced with a choice between evils:
Category D: Due to an error in judgement
Category E: Completely unintentional